1st Place: System Shock 1
Reason: This is a hauntingly great example of how good the much maligned "techno" genre can be if its worked out properly. Go to a sshock fan site and download it all - NOW!
medical suite, reactor level and intro tune are all must-haves.
2nd Place: Unreal
Extremely good sampled music done in the DOS Screamtracker! I havent found any other tunes by Straylight - they seem to have disappeared but the Unreal 1 soundtrack was a real work of art.
3rd Place: Descent 2
With the likes of NiN and Type-0 negative working on tracks for this game it couldnt fail to impress, however the track that stands out for me is "cold reality" - top notch industrial stuff.
4th Place: Half Life
Half life boasts some excellent electronic/industrial tracks and although Opposing Force only has 3 half decent tracks they are still pretty good - get hold of them.
5th Place: Deus Ex
Great signiature tune, generally good atmospheric music throughout the game
5th Place: Freespace 1 & Freespace 2 breifings
The freespace music I have to say was rather bland, but well produced and I escecially liked three of the brieifing tunes - although they're too damn short!