<PAGE>   1

   As filed with the Securities and Exchange Commission on September 29, 1999
                                                      Registration No. 333-_____
================================================================================

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                               -------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933

                               -------------------

                                 CYBERGOLD, INC.
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                 <C>                            <C>
           California                           7311                   94-3212392
  (State or other jurisdiction      (Primary Standard Industrial     (IRS Employer
of incorporation or organization)    Classification Code Number)   Identification No.)
</TABLE>

                            1330 Broadway, 12th Floor
                            Oakland, California 94612
               (Address of principal executive offices) (Zip Code)

                               -------------------

                                 CYBERGOLD, INC.
                             1996 STOCK OPTION PLAN
                       1999 OMNIBUS EQUITY INCENTIVE PLAN
                        1999 EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the Plans)

                               -------------------

                             A. Nathaniel Goldhaber
                      President and Chief Executive Officer
                                 CYBERGOLD, INC.
                            1330 Broadway, 12th Floor
                            Oakland, California 94612
                     (Name and address of agent for service)
                                 (510) 836-8700
          (Telephone number, including area code, of agent for service)

                               -------------------

<TABLE>
<CAPTION>
                                         CALCULATION OF REGISTRATION FEE
==================================================================================================================
           Securities                         Amount        Proposed Minimum     Proposed Maximum      Amount of
              to be                            to be         Offering Price     Aggregate Offering    Registration
           Registered                      Registered(1)      per Share(2)           Price(2)             Fee
           ----------                      -------------    ----------------    ------------------    ------------
<S>                                          <C>                 <C>                <C>                    <C>
1996 Stock Option Plan and
1999 Omnibus Equity Incentive Plan
     Options                                 3,095,168             N/A                   N/A                  N/A
     Common Stock (par value $.0001)         3,095,168           $9.00              $27,856,512            $7,745

1999 Employee Stock Purchase Plan
     Rights to Purchase                        300,000             N/A                   N/A                  N/A
     Common Stock (par value $.0001)           300,000            $9.00              $2,700,000              $751
</TABLE>

(1)  This Registration Statement shall also cover any additional shares of
     Common Stock which become issuable under the 1999 Omnibus Equity Incentive
     Plan, the 1999 Employee Stock Purchase Plan, or the 1996 Stock Option Plan
     by reason of any stock dividend, stock split, recapitalization or other
     similar transaction effected without the receipt of consideration which
     results in an increase in the number of the outstanding shares of Common
     Stock of Cybergold, Inc.

(2)  Calculated solely for purposes of this offering under Rule 457(h) of the
     Securities Act of 1933, as amended, on the basis of the fair market value
     per share of Common Stock of Cybergold, Inc. on September 22, 1999.


<PAGE>   2

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3. Incorporation of Documents by Reference

     Cybergold, Inc. (the "Registrant") hereby incorporates by reference into
this Registration Statement the following documents previously filed with the
Securities and Exchange Commission (the "SEC"):

     (a)  The Registrant's prospectus filed with the SEC pursuant to Rule 424(b)
          under the Securities Act of 1933, as amended (the "1933 Act"), in
          connection with Registration Statement No. 333-79067 on Form S-1 filed
          with the SEC on May 21, 1999, together with any and all amendments
          thereto, in which there are set forth audited financial statements for
          the Registrant's fiscal years ended December 31, 1997 and 1998, and

     (b)  The description of the Registrant's outstanding Common Stock contained
          in the Registrant's Registration Statement No. 333-79067 on Form
          8-A12G filed with the SEC on September 14, 1999, pursuant to Section
          12 of the 1934 Act, including any amendment or report filed for the
          purpose of updating such description.

     All reports and definitive proxy or information statements filed pursuant
to Section 13(a), 13(c), 14 or 15(d) of the 1934 Act after the date of this
Registration Statement and prior to the filing of a post-effective amendment
which indicates that all securities offered hereby have been sold or which
deregisters all securities then remaining unsold shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of filing of such documents.

Item 4. Description of Securities

     Not Applicable.

Item 5. Interests of Named Experts and Counsel

     Not Applicable.

Item 6. Indemnification of Directors and Officers

     Section 145 of the Delaware General Corporation Law authorizes a court to
award or a corporation's Board of Directors to grant indemnification to
directors and officers in terms sufficiently broad to permit such
indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the 1933 Act. The
Registrant's Bylaws provide for mandatory indemnification of its directors and
permissible indemnification of officers, employees and other agents to the
maximum extent permitted by the Delaware General Corporation Law. The
Registrant's Certificate of Incorporation provides that, pursuant to Delaware
law, its directors shall not be liable for monetary damages for breach of their
fiduciary duty as directors to the Registrant and its stockholders. This
provision in the Certificate of Incorporation does not eliminate the fiduciary
duty of the directors, and, in appropriate circumstances, equitable remedies
such as injunctive or other forms of non-monetary relief will remain available
under Delaware law. In addition, each director will continue to be subject to
liability for breach of the director's duty of loyalty to the Registrant for
acts or omissions not in good faith or involving intentional misconduct, for
knowing violations of law, for actions leading to improper personal benefit to
the director and for payment of dividends or approval of stock repurchases or
redemptions that are unlawful under Delaware law. The provision also does not
affect a director's responsibilities under any other law, such as the federal
securities laws or state or federal environmental laws. The Registrant has
entered into Indemnification Agreements with its directors. The Indemnification
Agreements provide the Registrant's directors with further indemnification to
the maximum extent permitted by the Delaware General Corporation Law.


                                      II-2

<PAGE>   3

Item 7. Exemption from Registration Claimed

     Not Applicable.

Item 8. Exhibits

<TABLE>
<CAPTION>
Exhibit Number      Exhibit
- --------------      -------
<S>                 <C>
     4              Instrument Defining Rights of Stockholders. Reference is made to
                    Registrant's Registration Statement No. 333-79067 on Form 8-A12G,
                    which is incorporated herein by reference pursuant to Item 3(b)
                    of this Registration Statement.

     5              Opinion and consent of Gunderson Dettmer Stough Villeneuve
                    Franklin  & Hachigian, LLP.

    23.1            Consent of Arthur Andersen LLP, Independent Public Accountants.

    23.2            Consent of Gunderson Dettmer Stough Villeneuve Franklin &
                    Hachigian, LLP is contained in Exhibit 5.

    24              Power of Attorney. Reference is made to page II-4 of this
                    Registration Statement.
</TABLE>

Item 9. Undertakings

     A.   The undersigned Registrant hereby undertakes: (1) to file, during any
period in which offers or sales are being made, a post-effective amendment to
this Registration Statement (i) to include any prospectus required by Section
10(a)(3) of the 1933 Act, (ii) to reflect in the prospectus any facts or events
arising after the effective date of this Registration Statement (or the most
recent post-effective amendment thereof) which, individually or in the
aggregate, represent a fundamental change in the information set forth in this
Registration Statement and (iii) to include any material information with
respect to the plan of distribution not previously disclosed in this
Registration Statement or any material change to such information in this
Registration Statement; provided, however, that clauses (1)(i) and (1)(ii) shall
not apply if the information required to be included in a post-effective
amendment by those paragraphs is contained in periodic reports filed with or
furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d)
of the 1934 Act that are incorporated by reference in this Registration
Statement; (2) that for the purpose of determining any liability under the 1933
Act each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities offered therein and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof and (3) to remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the Registrant's 1999 Omnibus Equity Incentive Plan, 1999
Employee Stock Purchase Plan, and 1996 Stock Option Plan.

     B.   The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the 1933 Act, each filing of the Registrant's
annual report pursuant to Section 13(a) or Section 15(d) of the 1934 Act that is
incorporated by reference in this Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     C.   Insofar as indemnification for liabilities arising under the 1933 Act
may be permitted to directors, officers or controlling persons of the Registrant
pursuant to the indemnification provisions summarized in Item 6 or otherwise,
the Registrant has been advised that, in the opinion of the SEC, such
indemnification is against public policy as expressed in the 1933 Act, and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the Registrant of expenses incurred
or paid by a director, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the 1933 Act and will be governed by the final
adjudication of such issue.


                                      II-3

<PAGE>   4

                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Berkeley, State of California on this 29th day of
September, 1999.


                                       CYBERGOLD, INC.


                                       By: /s/ A. NATHANIEL GOLDHABER
                                          --------------------------------------
                                          A. Nathaniel Goldhaber
                                          President, Chief Executive Officer and
                                          Chairman of the Board


                                POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS:

     That the undersigned officers and directors of Cybergold, Inc., a Delaware
corporation, do hereby constitute and appoint A. Nathaniel Goldhaber and John D.
Steuart, and either of them, the lawful attorneys-in-fact and agents with full
power and authority to do any and all acts and things and to execute any and all
instruments which said attorneys and agents, and either one of them, determine
may be necessary or advisable or required to enable said corporation to comply
with the Securities Act of 1933, as amended, and any rules or regulations or
requirements of the Securities and Exchange Commission in connection with this
Registration Statement. Without limiting the generality of the foregoing power
and authority, the powers granted include the power and authority to sign the
names of the undersigned officers and directors in the capacities indicated
below to this Registration Statement, to any and all amendments, both
pre-effective and post-effective, and supplements to this Registration
Statement, and to any and all instruments or documents filed as part of or in
conjunction with this Registration Statement or amendments or supplements
thereof, and each of the undersigned hereby ratifies and confirms all that said
attorneys and agents, or either one of them, shall do or cause to be done by
virtue hereof. This Power of Attorney may be signed in several counterparts.

     IN WITNESS WHEREOF, each of the undersigned has executed this Power of
Attorney as of the date indicated.

     Pursuant to the requirements of the Securities Act of 1933, as amended,
this Registration Statement has been signed below by the following persons in
the capacities and on the dates indicated.

<TABLE>
<CAPTION>
Signature                                   Title                          Date
- ---------                                   -----                          ----
<S>                           <C>                                     <C>
/s/ A. NATHANIEL GOLDHABER    President, Chief Executive Officer      September 29, 1999
- ---------------------------   and Chairman of the Board
A. Nathaniel Goldhaber        (Principal Executive Officer)

/s/ JOHN D. STEUART           Chief Financial Officer (Principal      September 29, 1999
- ---------------------------   Financial and Accounting Officer)
John D. Steuart
</TABLE>


                                      II-4

<PAGE>   5

<TABLE>
<CAPTION>
Signature                                     Title                          Date
- ---------                                     -----                          ----
<S>                                  <C>                                     <C>
/s/ CHRISTOPHER D. ALAFI, PH.D.       Director                                September 29, 1999
- -------------------------------
Christopher D. Alafi, Ph.D.

/s/ JAY CHIAT                         Director                                September 29, 1999
- ---------------------------
Jay Chiat

/s/ GARRETT P. GRUENER                Director                               September 29, 1999
- ---------------------------
Garrett P. Gruener

/s/ REGIS P. MCKENNA                  Director                               September 29, 1999
- ---------------------------
Regis P. McKenna

/s/ ALAN SALZMAN                      Director                               September 29, 1999
- ---------------------------
Alan Salzman

/s/ PETER S. SEALEY, PH.D.            Director                               September 29, 1999
- ---------------------------
Peter S. Sealey, Ph.D.
</TABLE>


                                      II-5

<PAGE>   6

                                  EXHIBIT INDEX

<TABLE>
<CAPTION>
Exhibit Number      Exhibit
- --------------      -------
<S>                 <C>
     4              Instrument Defining Rights of Stockholders. Reference is made to
                    Registrant's Registration Statement No. 333-79067 on Form 8-A12G,
                    which is incorporated herein by reference pursuant to Item 3(b)
                    of this Registration Statement.

     5              Opinion and consent of Gunderson Dettmer Stough Villeneuve
                    Franklin  & Hachigian, LLP.

    23.1            Consent of Arthur Andersen LLP, Independent Public Accountants.

    23.2            Consent of Gunderson Dettmer Stough Villeneuve Franklin &
                    Hachigian, LLP is contained in Exhibit 5.

    24              Power of Attorney. Reference is made to page II-4 of this
                    Registration Statement.
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 18076}]
{"company-data": {"conformed-name": "CYBERGOLD INC", "cik": "0001086937", "assigned-sic": "7311"}, "filing-values": {"form-type": "S-8", "file-number": "333-88053", "film-number": "99719940"}, "business-address": {"street1": "C/O CYBERGOLD INC", "street2": "2921 ADELINE STREET", "city": "BERKELEY", "state": "CA", "zip": "94703", "phone": "5108455000"}, "mail-address": {"street1": "2921 ADELINE STREET", "street2": "C/O CYBERGOLD INC", "city": "BERKELEY", "state": "CA", "zip": "94703"}}
1

   As filed with the Securities and Exchange Commission on September 29, 1999
                                                      Registration No. 333-_____
================================================================================

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                               -------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933

                               -------------------

                                 CYBERGOLD, INC.
             (Exact name of registrant as specified in its charter)
California                           7311                   94-3212392
  (State or other jurisdiction      (Primary Standard Industrial     (IRS Employer
of incorporation or organization)    Classification Code Number)   Identification No.)
1330 Broadway, 12th Floor
                            Oakland, California 94612
               (Address of principal executive offices) (Zip Code)

                               -------------------

                                 CYBERGOLD, INC.
                             1996 STOCK OPTION PLAN
                       1999 OMNIBUS EQUITY INCENTIVE PLAN
                        1999 EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the Plans)

                               -------------------

                             A. Nathaniel Goldhaber
                      President and Chief Executive Officer
                                 CYBERGOLD, INC.
                            1330 Broadway, 12th Floor
                            Oakland, California 94612
                     (Name and address of agent for service)
                                 (510) 836-8700
          (Telephone number, including area code, of agent for service)

                               -------------------
CALCULATION OF REGISTRATION FEE
==================================================================================================================
           Securities                         Amount        Proposed Minimum     Proposed Maximum      Amount of
              to be                            to be         Offering Price     Aggregate Offering    Registration
           Registered                      Registered(1)      per Share(2)           Price(2)             Fee
           ----------                      -------------    ----------------    ------------------    ------------
1996 Stock Option Plan and
1999 Omnibus Equity Incentive Plan
     Options                                 3,095,168             N/A                   N/A                  N/A
     Common Stock (par value $.0001)         3,095,168           $9.00              $27,856,512            $7,745

1999 Employee Stock Purchase Plan
     Rights to Purchase                        300,000             N/A                   N/A                  N/A
     Common Stock (par value $.0001)           300,000            $9.00              $2,700,000              $751
(1)  This Registration Statement shall also cover any additional shares of
     Common Stock which become issuable under the 1999 Omnibus Equity Incentive
     Plan, the 1999 Employee Stock Purchase Plan, or the 1996 Stock Option Plan
     by reason of any stock dividend, stock split, recapitalization or other
     similar transaction effected without the receipt of consideration which
     results in an increase in the number of the outstanding shares of Common
     Stock of Cybergold, Inc.

(2)  Calculated solely for purposes of this offering under Rule 457(h) of the
     Securities Act of 1933, as amended, on the basis of the fair market value
     per share of Common Stock of Cybergold, Inc. on September 22, 1999.
2

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference

     Cybergold, Inc. (the "Registrant") hereby incorporates by reference into
this Registration Statement the following documents previously filed with the
Securities and Exchange Commission (the "SEC"):

     (a)  The Registrant's prospectus filed with the SEC pursuant to Rule 424(b)
          under the Securities Act of 1933, as amended (the "1933 Act"), in
          connection with Registration Statement No. 333-79067 on Form S-1 filed
          with the SEC on May 21, 1999, together with any and all amendments
          thereto, in which there are set forth audited financial statements for
          the Registrant's fiscal years ended December 31, 1997 and 1998, and

     (b)  The description of the Registrant's outstanding Common Stock contained
          in the Registrant's Registration Statement No. 333-79067 on Form
          8-A12G filed with the SEC on September 14, 1999, pursuant to Section
          12 of the 1934 Act, including any amendment or report filed for the
          purpose of updating such description.

     All reports and definitive proxy or information statements filed pursuant
to Section 13(a), 13(c), 14 or 15(d) of the 1934 Act after the date of this
Registration Statement and prior to the filing of a post-effective amendment
which indicates that all securities offered hereby have been sold or which
deregisters all securities then remaining unsold shall be deemed to be
incorporated by reference into this Registration Statement and to be a part
hereof from the date of filing of such documents.

Item 4. Description of Securities

     Not Applicable.

Item 5. Interests of Named Experts and Counsel

     Not Applicable.

Item 6. Indemnification of Directors and Officers

     Section 145 of the Delaware General Corporation Law authorizes a court to
award or a corporation's Board of Directors to grant indemnification to
directors and officers in terms sufficiently broad to permit such
indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the 1933 Act. The
Registrant's Bylaws provide for mandatory indemnification of its directors and
permissible indemnification of officers, employees and other agents to the
maximum extent permitted by the Delaware General Corporation Law. The
Registrant's Certificate of Incorporation provides that, pursuant to Delaware
law, its directors shall not be liable for monetary damages for breach of their
fiduciary duty as directors to the Registrant and its stockholders. This
provision in the Certificate of Incorporation does not eliminate the fiduciary
duty of the directors, and, in appropriate circumstances, equitable remedies
such as injunctive or other forms of non-monetary relief will remain available
under Delaware law. In addition, each director will continue to be subject to
liability for breach of the director's duty of loyalty to the Registrant for
acts or omissions not in good faith or involving intentional misconduct, for
knowing violations of law, for actions leading to improper personal benefit to
the director and for payment of dividends or approval of stock repurchases or
redemptions that are unlawful under Delaware law. The provision also does not
affect a director's responsibilities under any other law, such as the federal
securities laws or state or federal environmental laws. The Registrant has
entered into Indemnification Agreements with its directors. The Indemnification
Agreements provide the Registrant's directors with further indemnification to
the maximum extent permitted by the Delaware General Corporation Law.

                                      II-2
3

Item 7. Exemption from Registration Claimed

     Not Applicable.

Item 8. Exhibits
Exhibit Number      Exhibit
- --------------      -------
4              Instrument Defining Rights of Stockholders. Reference is made to
                    Registrant's Registration Statement No. 333-79067 on Form 8-A12G,
                    which is incorporated herein by reference pursuant to Item 3(b)
                    of this Registration Statement.

     5              Opinion and consent of Gunderson Dettmer Stough Villeneuve
                    Franklin  & Hachigian, LLP.

    23.1            Consent of Arthur Andersen LLP, Independent Public Accountants.

    23.2            Consent of Gunderson Dettmer Stough Villeneuve Franklin &
                    Hachigian, LLP is contained in Exhibit 5.

    24              Power of Attorney. Reference is made to page II-4 of this
                    Registration Statement.
Item 9. Undertakings

     A.   The undersigned Registrant hereby undertakes: (1) to file, during any
period in which offers or sales are being made, a post-effective amendment to
this Registration Statement (i) to include any prospectus required by Section
10(a)(3) of the 1933 Act, (ii) to reflect in the prospectus any facts or events
arising after the effective date of this Registration Statement (or the most
recent post-effective amendment thereof) which, individually or in the
aggregate, represent a fundamental change in the information set forth in this
Registration Statement and (iii) to include any material information with
respect to the plan of distribution not previously disclosed in this
Registration Statement or any material change to such information in this
Registration Statement; provided, however, that clauses (1)(i) and (1)(ii) shall
not apply if the information required to be included in a post-effective
amendment by those paragraphs is contained in periodic reports filed with or
furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d)
of the 1934 Act that are incorporated by reference in this Registration
Statement; (2) that for the purpose of determining any liability under the 1933
Act each such post-effective amendment shall be deemed to be a new registration
statement relating to the securities offered therein and the offering of such
securities at that time shall be deemed to be the initial bona fide offering
thereof and (3) to remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the Registrant's 1999 Omnibus Equity Incentive Plan, 1999
Employee Stock Purchase Plan, and 1996 Stock Option Plan.

     B.   The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the 1933 Act, each filing of the Registrant's
annual report pursuant to Section 13(a) or Section 15(d) of the 1934 Act that is
incorporated by reference in this Registration Statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     C.   Insofar as indemnification for liabilities arising under the 1933 Act
may be permitted to directors, officers or controlling persons of the Registrant
pursuant to the indemnification provisions summarized in Item 6 or otherwise,
the Registrant has been advised that, in the opinion of the SEC, such
indemnification is against public policy as expressed in the 1933 Act, and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the Registrant of expenses incurred
or paid by a director, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the 1933 Act and will be governed by the final
adjudication of such issue.

                                      II-3
4

                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Berkeley, State of California on this 29th day of
September, 1999.

                                       CYBERGOLD, INC.

                                       By: /s/ A. NATHANIEL GOLDHABER
                                          --------------------------------------
                                          A. Nathaniel Goldhaber
                                          President, Chief Executive Officer and
                                          Chairman of the Board

                                POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS:

     That the undersigned officers and directors of Cybergold, Inc., a Delaware
corporation, do hereby constitute and appoint A. Nathaniel Goldhaber and John D.
Steuart, and either of them, the lawful attorneys-in-fact and agents with full
power and authority to do any and all acts and things and to execute any and all
instruments which said attorneys and agents, and either one of them, determine
may be necessary or advisable or required to enable said corporation to comply
with the Securities Act of 1933, as amended, and any rules or regulations or
requirements of the Securities and Exchange Commission in connection with this
Registration Statement. Without limiting the generality of the foregoing power
and authority, the powers granted include the power and authority to sign the
names of the undersigned officers and directors in the capacities indicated
below to this Registration Statement, to any and all amendments, both
pre-effective and post-effective, and supplements to this Registration
Statement, and to any and all instruments or documents filed as part of or in
conjunction with this Registration Statement or amendments or supplements
thereof, and each of the undersigned hereby ratifies and confirms all that said
attorneys and agents, or either one of them, shall do or cause to be done by
virtue hereof. This Power of Attorney may be signed in several counterparts.

     IN WITNESS WHEREOF, each of the undersigned has executed this Power of
Attorney as of the date indicated.

     Pursuant to the requirements of the Securities Act of 1933, as amended,
this Registration Statement has been signed below by the following persons in
the capacities and on the dates indicated.
Signature                                   Title                          Date
- ---------                                   -----                          ----
/s/ A. NATHANIEL GOLDHABER    President, Chief Executive Officer      September 29, 1999
- ---------------------------   and Chairman of the Board
A. Nathaniel Goldhaber        (Principal Executive Officer)

/s/ JOHN D. STEUART           Chief Financial Officer (Principal      September 29, 1999
- ---------------------------   Financial and Accounting Officer)
John D. Steuart
II-4
5
Signature                                     Title                          Date
- ---------                                     -----                          ----
/s/ CHRISTOPHER D. ALAFI, PH.D.       Director                                September 29, 1999
- -------------------------------
Christopher D. Alafi, Ph.D.

/s/ JAY CHIAT                         Director                                September 29, 1999
- ---------------------------
Jay Chiat

/s/ GARRETT P. GRUENER                Director                               September 29, 1999
- ---------------------------
Garrett P. Gruener

/s/ REGIS P. MCKENNA                  Director                               September 29, 1999
- ---------------------------
Regis P. McKenna

/s/ ALAN SALZMAN                      Director                               September 29, 1999
- ---------------------------
Alan Salzman

/s/ PETER S. SEALEY, PH.D.            Director                               September 29, 1999
- ---------------------------
Peter S. Sealey, Ph.D.
II-5
6

                                  EXHIBIT INDEX
Exhibit Number      Exhibit
- --------------      -------
4              Instrument Defining Rights of Stockholders. Reference is made to
                    Registrant's Registration Statement No. 333-79067 on Form 8-A12G,
                    which is incorporated herein by reference pursuant to Item 3(b)
                    of this Registration Statement.

     5              Opinion and consent of Gunderson Dettmer Stough Villeneuve
                    Franklin  & Hachigian, LLP.

    23.1            Consent of Arthur Andersen LLP, Independent Public Accountants.

    23.2            Consent of Gunderson Dettmer Stough Villeneuve Franklin &
                    Hachigian, LLP is contained in Exhibit 5.

    24              Power of Attorney. Reference is made to page II-4 of this
                    Registration Statement.