You just sold something on e-bay and now the winner won't pay up.  What do you do?  I'm not sure what the legality of this kind of Social Engineering hack is, but I believe you've got to give it points for elegance.

Here's the link to the lifehacker.com post (I can't find the original Reddit post.)

Reddit user "BadgerMatt" (we'll call him Matt for short) recently posted a story about how he tried to sell tickets to a sporting event on eBay, but when the auction was won the winning bidder backed out of the deal. In some cases this is mainly an inconvenience and you can re-list the item, but Matt was selling tickets to a sporting event and no longer had the time to do that. With the losing bidders uninterested in the tickets, he was going to end up stuck with tickets he couldn't use and a deadbeat bidder who was unwilling to honor their contract. Rather than give up, Matt decided to trick her into paying:

I created a new eBay account, "Payback" we'll call it, and sent her a message: "Hi there, I noticed you won an auction for 4 [sporting event] tickets. I meant to bid on these but couldn't get to a computer. I wanted to take my son and dad and would be willing to give you $1,000 for the tickets. I imagine that you've already made plans to attend, but I figured it was worth a shot."

The woman agreed, but for $1,100. She paid for the auction, received the tickets, and then Matt (of course) never re-purchased them. Needless to say, the woman was angry. Perhaps it was the wrong thing for the right reasons, but I'm mostly jealous I never thought of it back when I still sold things on eBay.