old_contents: #!/usr/bin/env python
  
  import os, sys, time
  
  folders = sys.argv[1:]
  
  currSize = dict((x, 0) for x in folders)
  totalSize = dict((x, 0) for x in folders)
  maxSize = dict((x, 0) for x in folders)
  
  fmts = "%*s  %13s  %13s  %13s"
  fmtd = "%*s  %13d  %13d  %13d"
  
  n = 0
  while True:
      print fmts % (15, "dir", "size", "avg", "max")
      n += 1
      for folder in folders:
          bytes = sum( os.path.getsize(os.path.join(dirpath, filename)) for dirpath, dirnames, filenames in os.walk( folder ) for filename in filenames )
          currSize[folder] = bytes
          totalSize[folder] += bytes
          maxSize[folder] = max(maxSize[folder], bytes)
          avg = totalSize[folder] / n
          print fmtd % (15, folder, bytes, avg, maxSize[folder])
      print ""
      time.sleep(1)
  
new_contents: #!/usr/bin/env python
  
  import os, sys, time
  
  folders = sys.argv[1:]
  nameWidth = max([len(f) for f in folders])
  
  currSize = dict((x, 0) for x in folders)
  totalSize = dict((x, 0) for x in folders)
  maxSize = dict((x, 0) for x in folders)
  
  fmts = "%*s  %13s%s  %13s%s  %13s%s"
  
  n = 0
  while True:
      print fmts % (nameWidth, "directory", "curr size", " ", "avg size", " ", "max size", " ")
      n += 1
      for folder in folders:
          bytes = sum( os.path.getsize(os.path.join(dirpath, filename)) 
                          for dirpath, dirnames, filenames in os.walk( folder ) 
                          for filename in filenames )
          oldSize = currSize[folder]
          oldAvg = 1 if n == 1 else totalSize[folder]/(n-1)
          oldMax = maxSize[folder]
          currSize[folder] = bytes
          totalSize[folder] += bytes
          maxSize[folder] = max(maxSize[folder], bytes)
          avg = totalSize[folder] / n
          print fmts % (nameWidth, folder, 
                          "{:,}".format(bytes), "+" if bytes > oldSize else "-" if bytes < oldSize else " ",  
                          "{:,}".format(avg), "+" if avg > oldAvg else "-" if avg < oldAvg else " ", 
                          "{:,}".format(maxSize[folder]), "+" if maxSize[folder] > oldMax else " ")
      print ""
      time.sleep(2)
  
subject: Add formatting to directory monitor.