Offer free downloads of your book?

Saw a guy on BookTV last night talking about CC licensing. You can license any copyrighted work for free downloads, licenses can/cannot allow changes, CC licenses allow free downloads only for non-commercial uses; CC-licensed matl can be passed along to others. It’s Creative Copyright, but don’t the URL at hand.

Has anyone ever used something like CC licensing to offer free downloads of your book for publicity purposes? This strategy is being used by some bands. And Nine Inch Nails did something like this for promo — and results were huge sales of CDs, etc.

Any comments? Suggestions?