http://www.horde.org/ An application framework with a number of groupware-related applications Built on top of PEAR, including PEAR::DB for database abstraction IMP: Webmail Jonah: Portal Kronolith: Calendar WHUPS: Problem Tracking Turba: Address book, contact management Chora: CVS viewer Mnemo: Note manager Nag: Task manager Sork: Account management Orator: Presentation software