I am surprised no one ever mentioned the Mechwarrior series. Personally, I think this is the best ever musical score for a computer (video) game. It is so explosive at times and yet so tranquil on occasions. Grim Fandango's off beat jazzy / mexican style score was also very "exceptionnel" - as the french would say. Another very interesting score was the cello variations in Max Payne (can''t remember if the original or the sequel). Also, very beautiful music accompanied the Longest Journey series. I have copied all above and often listen in the car or at work when I stay late and I am alone in the office.