As per tradition, Here is a link to the 2011 SXSW Music Showcase Torrent. This year the torrent contains 771 files totaling 4.41 GB of music from bands playing at this years South By Southwest Music & Media Conference. Keep a close eye on Greg Hewgill’s website because he will most likely be putting up a second torrent with more bands in early March.
I have yet to find a service that is streaming this year’s files.
UPDATE: The second torrent has been released. It has an additional 448 files (2.8 GB)