Loved the Space Hulk boardgame with expansions - as well as Space Crusade. Never found any of the computer versions very interesting - as the core boardgame is quite simplistic and limited in scope - and they're all based on the core game.

I'd love an expansive turn-based version - with the features from the expansion material and that campaign book you could get for it.

Other than that, I think the setting has a lot of potential for an Aliens/System Shock type of game - heavy on atmosphere and exploration.