Until September 7, 2010 you can list on Ebay for free. Normally you have to pay a listing fee on top of the percentage Ebay gets when your item sells, but now you can list it for free. You only pay Ebay their cut if the item sells. If it doesn’t, then you’re not out the listing fee.
See more details here. This is a great way to clean out some of those things you’ve been wanting to get rid of!