The Amazon MP3 Store offers downloads of Brian Eno's Neroli MP3 Album for 99 cents. (iTunes charges the same.) That's the lowest price we could find for this 1-track (57:56 minutes) DRM-free album, which was released in 2006. Amazon MP3 Downloader is required.

Of note, this album qualifies for 20GB of online storage for free via the new Amazon Cloud Drive.