Starbucks just introduced a great new spiff when you purchase a coffee in one of their stores, the "song of the day." So far, I've picked up free downloads from Bob Dylan, Keith Urban, KT Tunstall, and Joni Mitchell.
This is actually a small bit of a broader marketing partnership between Apple and Starbucks. Apple is no providing free access to the iTunes Music store (have you ever heard of a store charging for entrance?!). The cool thing about it though is that you can also see on iTunes what is playing at the moment in the store (and make your purchase for $.99).
I think its a great idea. The free songs are only available through November 7th AND you have to ask for them. They don't just give them out.