Gore - The Ultimate Soldier is an online multi-player game with a goal of providing classic hard core FPS action

a first-person shooter computer game that uses the Ageia PhysX engine.

Midway’s Area 51 is now available to download and play for FREE as an ad supported game. This is a full version with no time expiration sponsored by the US Air Force.

Celestial Impact is a team based multiplayer first person shooter (FPS) taking place on various asteroids floating in space.

Urban Terror can be described as a Hollywood tactical shooter; somewhat realism based, but the motto is "fun over realism". This results in a very unique, enjoyable and addictive game.

World of Padman (WoP) is an open source first-person shooter computer game

A GPL first-person shooter by Alientrap Software. with nine weapons, 24 official maps and over 240 community created maps, as well as 15 player models.

War Rock is a multiplayer online first-person shooter available free for download

America's Army is a video game owned by the United States Government and offers accurate FPS action

FEAR Combat is the multiplayer part of FEAR that has been released for free.