Magic Auction is run by Joe and Christine Tripi. You list your item and set an asking price. Visitors to the site can bid on the item. At the end of a week, if your item is sold, you send it to Joe and Chris who forward it to the buyer. Then a check for your asking price is sent to you.
More details are on their web site.
This sounds like a great way to clean out the magic closet without ever leaving home, and a terrific way to shop for tricks and books at a reduced price.