My favorite from couple of years ago was a guy who posted 'his left nut'.....slightly used....
After cleaning up the beverage that spewed from a bust of laughter when I ran across it, I promptly emailed him to inquire further.
It seems he had several recent successes in selling various items on Ebay. His friends and co-workers informed him that they bet he could sell his left nut if he wanted to, so he posted it for sale.
I bid but did not win the auction....