OGRE GPL'ed 3D Engine
Steve Streeting writes "Version 0.99b of OGRE (Object-oriented Graphics Rendering Engine) has been released! OGRE is a well designed, flexible and easy to use 3D engine released under the GNU Public License. This version adds highly customisable, scriptable particle systems, generic billboard support, compatibility with VC.Net, performance improvements and various bug fixes."
So, does the open source community have good computer game designers? I would argue that it not only does, but that many, if not most, commercial games available today originated as commercial copies of software originally developed freely by students and hobbyists. In fact, the open source process works extremely well for creating games that "flow" right; just look at the history of games like Nethack and how they have gotten tuned and enhanced by generations of students.
Good open source games take years to mature, but the end result is something that's a lot of fun and that you can play over and over again. That's not what can be said for most of the commercial stuff out there.