I think it would be cool if there were a super rare drop/end reward like an Auctioneer's Hat. If your Character wears the hat while using the Auction House, you can automatically win any single auctioned item by trading in your Auctioneer's Hat. The person that was auctioning that item would not receive any gold in the mail but would instead receive the Auctioneer's Hat for their use. When they use it, it passes to the next person, and so on.
What does the community think of this idea?