Napster: Convert DRM WMA files to MP3s
Contributed by AlexTheBeast 
Tagged: Windows Using virtuosa users can convert protected WMAs to unprotected mp3s.
Please note that this no long works. This hole has been closed. Some other methods are described in the comments below. I have also included some alternate methods here to help you with your music files.
Capture/RIP Music Streams for Easy, Free, Legal, and Tagged Music/MP3 Files
Ripcast is a inexpensive piece of software that will convert all audio formats into unprotected OGGs or MP3s. Try it!
Using sndrec32.exe to remove DRM from songs downloaded from napster
Use Google to Find Free MP3s, WMAs, OGGs, and Other Music Files
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Convert Music files between MP3, WMA, and WAV Easily and Quickly
Google: Find Free MP3s, WMAs, OGGs, and Other Music Files