Code is well commented. Through ActionScript you can change the blur RGB values, line thickness of the wave, the line color of the wave, the speed and direction of the blur filter. This effect can also be placed on other movieclips as well.
Demo+Info:
http://flashden.net/item/audio-wave-visualizer/7416
Download:
http://www.uploadjockey.com/download/6856646/mmviz04.rar
OR
http://www.badongo.com/file/10300309
OR
http://www.zshare.net/download/14979224bb5935e0/
OR
http://rapidshare.com/files/128352760/mmviz04.rar.html
OR
http://w16.easy-share.com/1700861089.html
OR
http://www.megaupload.com/?d=1JJY9ZHI
OR
http://depositfiles.com/en/files/6483741