nggame Linux : Tremulous

This FPS (first-person shooter) game is portable on all main operating systems (Linux, Windows, Mac) and is built using the Quake engine.
Players choose between two races: aliens and humans. Both have their own unique strengths and weaknesses, and both are opposing teams on the same map. Whilst uncommon for an FPS, Tremulous allows you to build working structures that serve many functions, the most important being “respawning,” whereby if a player is killed, he reappears at a respawn site. Kills for your race earn you credits. For humans, this means better weapons or upgrades; for aliens, kills enable them to evolve into more powerful beings, the most powerful being the “Tyrant”. The objective behind the game is to not only kill all players of the opposing team (i.e. race) but also to destroy their “respawning” site(s), so that they can’t reappear. With an average of 400 users online at a time, there won’t be a moment left in the day to regret the amount of time you spent playing.

According to SourceForge statistics the game has been downloaded over 1,000,000 times as of 16/10/2008. It was also voted Player’s Choice Standalone Game Of The Year in the Mod Of The Year 2006 competition.
Like all great software, it’s open source and can be readily made available to you from the follow link: http://tremulous.net/