If you like that, you should also check out Nexuiz if you have not yet. It is my favorite of all the Open Source 3D shooters I have tried so far. It comes close to the very fast gameplay I liked so much in Quake3.
Yeah, the game right now I don't think is that good. I was talking with the developer and he's planing on doing some big gameplay changes. I really hope it turns out good, that game has a lot of potential.
http://www.alientrap.org/games/nexuiz