Whether you're a Human or an Alien, you'll enjoy Tremulous, an exciting multi-player first-person shooter that incorporates elements of real-time strategy. Based on Quake 3, the goal in Tremulous, of course, is to wipe out the opposition. This is accomplished not only through killing them, but also by destroying their "spawn structures," effectively keeping them from replenishing their ranks.
Humans advance by receiving credits that allow them to purchase new weapons and upgrade their arsenals, while Alians evolve into new classes of beings, each more powerful than the last. Start as a Dretch and do your job well and you may soon evolve into a Basilisk, Marauder, or Tyrant. The game ends when all players on a team have been killed and all of their buildings have been destroyed.
Tremulous is a free, open source project that is available for Linux, Mac, and Windows. With a large support community and an active forum, there is a lot of interest in this exciting, award-winning game.