Konspire[2b]http://konspire.sourceforge.net/
MUTE
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Oh yeah, and the more crafty among you may be interested in this thing I just heard about: the iTMS-4-All Script.
Downhill Battle (http://www.downhillbattle.org/itmsscript/index.html) has released a script that allows users to surf the iTunes music store as if they're using iTunes. The creators want people to use the script in developing opensource applications. They suggest adding the ability for people using opensource filesharing clients like MUTE to use the iTunes interface to call up album and artist information as well as 30 second preview clips of songs found on P2P networks. Wow.