Perhaps i should suggest a FPS-game called Sauerbraten at

http://sauerbraten.org/

I have a load of fun with it, especially with the level editor :)

Robert van der Veeke Basugasubasubasu Basugasubakuhaku Gasubakuhakuhaku!! "Better is the enemy of good enough." Dr. Mikoyan of the Mikoyan Gurevich Design Bureau.