Pros

  • Supports exchange of events with Google calendar (via add-on)
  • Lightning add-on to Thunderbird e-mail client adds Sunbird calendar inside Thunderbird
  • Runs on Mac OS X, Windows, and Linux

Cons

  • Look is not Mac OS X style
  • Very limited notification options
  • Sunbird's to-do feature is no better than iCal's
  • Doesn't support Mac OS X technologies like iSync and Address Book

Manufacturer’s Website

http://www.mozilla.com