Sometimes, it's hard to tell what's a joke on eBay and what's not. Selling grilled cheese with the Virgin Mary's face is a joke. Selling Clay Aiken's handprints in cement is apparently not--high bidder is currently $10,800 (at least it's for charity):
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3851111309&category=58

...and there's an old left-handed bottle currently at $9,800, with two days left in the sale:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6131233770&category=890