Up at the SxSW Music Showcasing Artists page, a person can browse the over 1700 artists that performed. Most of the artists have submitted a track or two that you can listen to right from the site.  Being curious, I right-clicked the audio player used on the site and discovered it was by Jeroen Wijering.  I went to his site and discovered that he also has a Silverlight player as well.  It is dubbed as a WMV player, but it certainly could be used to play .mp3s or .asx playlist files. What I like is how easy he makes it for a person to incorporate the player into a website. Nice.