I've heard a lot of video game music in my day, and Nintendo game themes are up there in quality, but if I had to pick a single favorite tune or game, it would probably be something from Apogee's Rise of the Triad, released for the PC in the mid-90s.
Rise of the Triad was groundbreaking in terms of the quality of direct dial Modem play, Network multiplayer, and the ridiculous, breakneck speed of gameplay and gratuitous gore. It wasn't a Doom clone, it was an homage to Doom taken to the nth degree.
I spent YEARS playing this. It was a LAN party staple.
The tracks in particular, all composed by Lee Jackson and Bobby Prince, were extremely high quality MIDI for their day. While most of my generation, now 30-something PC gamers that were begging their parents for $3G for a college PC back in 1994 (really not for college, just to play Doom and get on this new-fangled thing called the Internet), will recognize Doom tracks more readily, I tend to think RotT was without peer for its music.
My three favorite tracks out of that are Oww, Mistache, and Shards. Oww is just some great free-form funk beat, Mist Ache has a very dark, almost Glen Danzig's Black Aria type symphonic feel, and Shards, I think, has a strong Castlevania vibe to it.
http://rott.classicgaming.gamespy.com/gallery/OWW.MID
http://rott.classicgaming.gamespy.com/gallery/SHARDS.MID
http://rott.classicgaming.gamespy.com/gallery/MISTACHE.MID
The first time I ever heard RotT in stereo MIDI, my jaw hit the floor. It was a reason to spend $200-300 on a Soundblaster AWE32 or 64 sound card.
