This is a game genre that has been almost forgotten (at the time).  I always thought that it would make a great FPS, there just so much to draw from, a wealth of movies and its generally ingrained in the western culture psyche.  I saw all the classic in a couple of day to get a real sense of it, read some books.  I still think this game could be made.

Lithtech, 3D Max and Photoshop.