This buyer purchased a small antique painting from me. She ripped the back off it (it was nailed on) and then contacted me demanding a refund because it wasn't a painting -rather a print. I agreed to the refund.

Then, on top of that she demanded that I pay the return shipping as well, and threatened that if I didn't pay the return she would leave negative feedback. I educated her about the Feedback Extortion policy on eBay and she didn't leave feedback.