DESCRIPTION:
The following information was taken from Wikipedia:

The Joyrex Tape, is a collection of unreleased tracks by Richard David James, better known under his pseudonym Aphex Twin. Although James has never admitted authorship of this supposedly unofficial album, at least one of its tracks are alternate versions (possibly demo versions) of tracks featured on the subsequently released Ventolin EP. Reportedly, James was having a house party, and passed out drunk on his couch. One of the guests stole the tape in an attempt to impress his girlfriend. The tape remained unreleased until recently, when it was leaked to the internet. The only place to find this music is through online P2P file-sharing. Some tracks on the album also bear resemblance to those of his EP Ventolin and the unreleased album Melodies from Mars. Many of these tracks have been played live, which leads many fans to believe that these are, in fact, his tracks. Track 4 was played live at the State-X New Forms festival. Track 5 and Track 9 were played at Melt 2006.

http://en.wikipedia.org/wiki/Joyrex_Tape
http://www.discogs.com/Aphex-Twin-Joyrex-Tape/release/2692716