Windows 8 users! (And Windows Phone too.) Download the Music Deals app from the Store. It'll show 50+ albums you can download for FREE from Xbox Music as a holiday promotion. (US only.) DRM free MP3s you can play anywhere. Good stuff representing every kind of music taste. So far I've downloaded U2, Rolling Stones, John Lennon, Bon Jovi, but there's rap and country and pop. This is an insane giveaway and I'm surprised it's not a bigger story on the internet.
If you're a Xbox Music Pass subscriber you get to choose from 100+ albums. I'm not and I still got to choose from 50+.