Screaming Penguin - Source Does Matter

Ok, somehow I missed this, and I suspect some other people might have too: The Wired CD was distributed with Wired Magazine a couple months ago, but you can download the tracks off the Creative Commons site. Open-Source tracks from David Byrne, The Beasties, Theivery Corporation (Ok, thats like 3 of my top 5 favorite artists right there), Paul Westerberg, Chuck D and more.

I highly recommend it.