Have you heard of Bookmooch? It's a site where you give away books for free- you even pay the postage, and you accrue points to mooch books off of other people for free. Great idea. I signed up a few months ago.
At first I was a little disappointed- no one seemed to want to give me any books. You can choose whether you are willing to send internationally or not. So far I have sent to Finland, Australia and the US (multiple times), all at the exorbitant Canada Post rate. Since the majority of the users are American, and most of them seem unwilling to send internationally it was looking like it was just a very expensive way for me to get rid of some extra books. But finally I'm started to get some books- today China Mieville's King Rat showed up in my mailbox! A beautiful, brand new trade paperback edition, no less. Sweet!