Shoutbox

To play the music through, you could simply use the ShoutCAST plugin included with Winamp.  (Which handles sending it and playing the music through.)

You should install a ShoutCAST server so you can send the information to the ShoutCAST server, which resends it into the listeners, usually the ShoutCAST server is over a fast internet line.  ShoutCAST does support listening over Windows Media Player.

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