From the site:
"Swappingtons is more of a treasure chest than just a www site! Inside, you will find all sorts of books, CDs and DVDs that other folks own, but wish to swap away. The way it works is simple: You list items that you don't want, and someone will swap you for those items. When they swap you, they transfer swap points to your account, and you mail them the item in question. Once you have the points, you can go and spend them on other items that other folks list on the site."