I just want to add that I really like the app "Collectible". It has a few things that I wish they would tweet but overall it list all sorts of auction sites that I've pr viouslynknow and a bunch I've never heard of.
I've been using it a lot lately trying to find my current whale, a baseball signed by Roberto Clemente in my price range. So far because of this site I am much more frequent an under bidder than I have ever been before.
Oh well, some day perhaps.
Drew