Midway has released full version of Area 51 allowing you to enjoy this sci-fi FPS developed by Inevitable Entertainment for free. The 2GB download can be found in CGO.ro, GH. 

Players take on the role of Lt. Nick Cross, a hazardous biological waste specialist sent to investigate. During his investigation, Lt. Cross stumbles across alien creatures and becomes infected with a biological mutagen that eventually transforms him into something not quite human. To save the earth and himself, Lt. Cross must fight to solve the enigma of Area 51. Area 51 takes the player through eight massive levels within a clandestine government complex. Combining intense combat, exploration, adventure, discovery, and puzzle solving, the game blends graphic violence with science fiction. As Lt. Cross, the player will discover secret areas and items, including the answers to this rumored government conspiracy.