Can open source games be any good? Most open source games are relatively small and simple, but the open source movement has produced some gems over the years, such as Battle for Wesnoth and Neverball. Blender’s Project Apricot is an example of a game developed using a new model of collaborative funding (DVD pre-orders) which was previously successfully used for open source 3D movie productions.
If you’re interested in keeping track of the progress of open source gaming, LibregameWiki is a great place to go. Sadly, many of the open source games it reports on aren’t considered notable enough for Wikipedia. In addition to the games themselves and the people who make them, LibregameWiki also writes about game development contests like RubyWeekend, which have recently become a source of lots of nice, open source mini-games.