What a Cool GAME!!!! and it works on linux

Review GameCloud
It's the live multiplayer portion of the game that sets Alien Arena 2006 apart. While the game's graphics are mostly based on the Quake 2 engine, it does use the Quake 3 Arena console code for any changes you might make...There's something to be said for creating a totally free game that, while without the graphical upgrades of a Doom 3 engine, still manages to be tons of fun to play around.

Installing (it's a .run file)

Playing: Duron 1GHz 256MB, Geforce 4MX 440 SE
Kernel 2.6.15 ck-7, Knoppix hd-install v3.7

More pics & Downloads (157MB +patches) on Alien Arena 2006 Official Site