This isn't about free music, its about free speech and file sharing of all types.
For example, there are hundreds of results of Messenger Plus! archived and current builds on Gnutella (the network used by Kazaa, LimeWire, BearShare and more).
Independent artists publish their music using P2P software. BearShare even has a
public publishing facility to do just that.
When you have a corrupted file or just one missing DLL that is stopping you from using that oh-so-amazing application, chances are you can find that file on a P2P network.
Anyway, that's my 2c rave.
Geez, I sound like a radio advertisment.
Update
@Patchou: Where do you find $15 CDs? Most things I see are twice that!