Sci-Fi

Sci-Fi themed games are games that are characteristic of science fiction literature; the narrative is dependent on the impact of scientific discoveries that do not yet exist in reality. Some games, such as those in the Half-Life series and Unreal series take place in a sci-fi universe that was created specifically for the purpose of the games. Others may take place in existing sci-fi universes, such as licensed Star Wars games. Common elements of sci-fi themed games include futuristic settings, high-tech items and weapons, and alien characters.

F.E.A.R. Combat

F.E.A.R. Combat is a multiplayer FPS from Monolith and Sierra. It is a repackaged version of the competitive multiplayer modes of F.E.A.R., and is downloadable and playable for free. It features 22 maps, 10 game modes, support for user-created content, and the ability to play against owners of the original game as well as other F.E.A.R. Combat players.

You can acquire a game key and download the game here:
http://www.joinfear.com/main

Battle Isle: The Andosia War

Battle Isle 4: The Andosia War is the fourth instalment of one of the oldest turn-based strategy franchises around and marks the series' transition into 3D territory.

Gun Metal

Gun Metal is a 3-D shooting game, released in 2003 for PC by the now defunct Rage Software Limited. The lead artist Nick Tipping and lead programmer Mark Featherstone on Gun Metal went on to form Moonpod.

The game allows players to pilot a futuristic mech which can transform into a plane. It is based around a war (sometime in the future) on a planet called Helios, where humans have settled. Enemy spacecraft have followed them from Earth and are attempting to exterminate the colony.

Command & Conquer 3: Tiberium Wars

The highly anticipated game Command & Conquer 3 Tiberium Wars is the next installment in the long running Real Time Strategy series from Electronic Arts.Play as either the Global Defense Initiative (GDI) or The Brotherhood of NOD for control of Tiberium and the World.

Serious Sam II

Serious Sam II (or Serious Sam 2) is a science fiction first-person shooter video game released for the PC and Xbox and the sequel to the 2001 computer game Serious Sam. It was designed and developed by Croteam and was released on October 11, 2005.
In the single-player campaign, the player assumes the role of hero Sam "Serious" Stone in his adventures against the forces of the extraterrestrial overlord, "Mental", who seeks to destroy humanity. Taking place after the events of Serious Sam: The Second

Carmageddon TDR 2000

Yes, it's the game literally... SOME of you asked for! And so, in the spirit of "well, alright then, if you insist..." we present the third game in the Carmageddon series, in the knowledge that some of you Carma fans out there would like to have a complete Carmageddon collection in your Steam library. Nothing wrong with that.

Anyway, here's what the blurb on the back of the DVD case had to say about Carmageddon: TDR 2000:

The world's most controversial racing game returns with incredible graphics, fantastic game play and even more outrageous fun!

Domination

Domination is the sequel to highly acclaimed turn-based strategy game Massive Assault. Domination features a renewed global conflict between the Free Nations Union and Phantom League in distant space colonies. The game is based on the Massive Assault

Also released as Massive Assault: Phantom Renaissance.

Cube 2: Sauerbraten

Cube 2: Sauerbraten (German for "sour roast", also known as Sauer) is a cross-platform, Quake-like first-person shooter that runs on Microsoft Windows, Linux, FreeBSD and Mac OS X using OpenGL and SDL. The game features single-player and multiplayer gameplay and contains an in-game level editor, its main feature. The game engine is free and open source software, under the zlib License, with commercial support available from the developer's own business counterpart, Dot3 Labs.