While the just-released Space Hulk has EA's (And Games Workshop's) permission to remake the title, it isn't based on the 1993 computer game at all. It's based on the board game.
It's an asymmetrical war-game basically. Set aboard the hulking pieces of space-wreckage known, for some reason, as Space Hulks in the Warhammer 40,000 universe, there's two groups. One one side, are the Terminator Space Marines who have guns. On the other sides, you have Genestealers, who don't. But they do have the sort of claws that can rend through the marines' Tactical Dreadnought Armour if they get close enough, lightning speed and endless numbers. While on the board-game version you could play either, in this one the computer plays the Genestealers leaving you to wrestle with the more sophisticated Space Marines.
Space Hulk is a freeware. The full client, editor and documentation can be downloaded via Rock Paper Shotgun (scroll down to the end of the review for a link.)