XSPF Web Music Player (Flash) - Plays MP3 on your website
Some examples of how to load the playlists:
http://www.z1n.com/public-files/music/xspf_player.swf?playlist_url=http://www.z1n.com/public-files/music/playlist.xspf&repeat_playlist=true
http://www.z1n.com/public-files/music/xspf_player_slim.swf?playlist_url=http://www.z1n.com/public-files/music/playlist.xspf&autoplay=true