Sven made a homepage for Pentabarf (German only in the moment). Pentabarf is a conference planning software written in PHP5 with a Postgres backend and some Apache RewriteRules. The software had its acid test with 21C3 - The Usual Suspects, the last years congress of CCC, it is also used for planning Datenspuren, the privacy symposium of CCC Dresden and What the Hack. Pentabarf has a nifty and powerful web interface with many configuration options and different export possibilities as XML, HTML, iCal and vCard. There is also a development feature I like: Pentabarf outputs errors rather to developers via Jabber then displaying errors to users. Pentabarf will still evolving, since there are some features missing like a proper release management for single events, a RT-like functionality or a more advandced ressouce planning. But anyway, I really like to work with it. The source is available through a subversion repository (svn://pentabarf.cccv.de/pentabarf/trunk). There is also a bug tracking system and a mailing list.