Facebook is giving away a 10 song sampler from Warped Tour. Here's what they say:
"Get 10 free songs from some of today's best alternative rock and punk bands including Bad Religion, NOFX, All Time Low, and Sing It Loud. Share the offer with your friends so they can become fans of the iTunes Facebook page and get their free Warped Tour Sampler too."
Get the sampler here. You need to have a Facebook account, and the offer is only valid for the US store.