2K Games today released the entire original score to BioShock as a free download. You can download the complete BioShock score (a 23MB zip file) by clicking here.
The 12-song original score was created by film, TV and game composer Garry Schyman and features a combination of early 20th-Century writing, aleatoric elements, musique concrete, traditional tonal and late romantic styles. In other words: Schyman combined a lot of elements to capture the distinct retro-futuristic aesthetic of the game.
Check it out. Really, it’s a good download. Keep in mind, though, that it’s not the complete soundtrack. The entire soundtrack includes actual retro music and even a song by Moby. This free download is just for the music score.