There's this website I discovered a while back called swaptree.com. It's a great resource if you have books or music or DVDs you no longer want and would like to trade them for other people's items. Oh, and did I mention it's free to join? Anyway, you post items you have and make a list of items you want and Swaptree matches your items with other people who have what you're looking for. I just think this is a great way of recycling. Sifting around the thrift store or Half Price Books can be fun, but you don't always find the exact item you want and this website makes it possible to find what you want for free! Yay! Who doesn't love free stuff?
Here's the link for more info: