Supposedly, there's this new program called Crystal Space 3D, which lets you make 3D games.  It's compatible with other 3D art programs, so if you had, say, Maya, and created an object in Maya, you could take it from there and put it in Crystal Space, and put it in a game!  Tigersan and other 3D artists, take note...!

http://www.crystalspace3d.org/tikiwiki/tiki-view_articles.php