Got some music for you here, sir.
- PurchaseSome good high energy buttrock that doesn't take itself seriously. Definitely better to experience the soundtrack for the first time while playing the game itself because the music emphasizes the outrageous action sequences in the game. But the music is still fine by itself.
- DownloadSlow but good Orchestral music emulating the sounds of the Industrial era pretty well. Though there are a few background music tracks in here like 'Village' or 'Cave' that are underwhelming.
- PurchaseTurn of the 19th Century Music again. Much better than Arcanum's but not as free.
- PurchaseEpic orchestra music about Greek Gods and other such divine matters.
- PurchaseI don't really know what the hell this is, metal-electronica? I like it though.
Since you didn't limit it to video games only:
(NSFW) Captain Murphy's Duality - Download
Psychedelic Hiphop released as a short film/music video on Adult Swim a few years back. The music and the video work together to show some cult imagined disjointed supernatural being that is Id manifest.