This is a cool site for people who consume lots of paperbacks, DVDs and/or console games. Here's how they describe it:

You know the books, CDs, DVDs, and other stuff you're finished with? Well, somebody wants them.

Zunafish® lets you trade your old media items for new titles you'd rather have. And, oh yeah-- it's fun, simple and dirt cheap: just a buck a trade! Easy and fun.

Just list the stuff you want to get rid of, pick the stuff you want to get, and watch the trade offers arrive!

I use this site now all the time. Whenever I finish reading a paperback, I list it on Zunafish. And every once in a while, an email comes in that says, "Someone wants your Zunafish item."

Then I click the link and I can see who wants my old book and what they've got to trade. If I like something they've got, a couple more clicks and the trade is initiated.

You set up an account, and they charge $1.00 to make a trade. They even print out a shipping label for you, and tell you what the postage costs.

The net is that it typically costs $3-$4 including postage for me to get a new book. And it's super convenient. They have a feedback system, so you see if people who want to trade with you are rated positively by others who have traded with them.

http://zunafish.com