Check it out. The book blogger at In the Shadow of Mt. TBR is hosting a contest to give away gift cards for books!
Visit the blog, but don't sign up, because that lowers my chances! Just kidding! Definitely sign up!
I like his reason for hosting this contest: authors generally don't make much money anyway and websites like PaperBackSwap (which I love) lowers their income even more because people are trading books instead of purchasing them new so the author gets his due royalties. I love PBS, but I always feel a little guilty swapping books.