Have you seen Edgeio? It’s run by Mike Arrington of TechCrunch fame, and it involves selling things, listing things, looking for things. To me, it’s a sleeker, more streamlined rendition of (I bet Mike cringes often) Craigslist. I like the basic idea though. Use RSS to drive information to one aggregate place without having to silo the information within that site.
So, if you have something to sell, Edgeio says to make sure you tag it “listing” for them to notice it. Also, there’s a spot on the main page to enter the URL where you posted the listing.
Right now at least, while it’s still so small, it’s really easy to search and find things you might be interested in. To me, it feels like eBay before that got massive.
Check it out, if you’ve got a listing you want to sell.