Dealing with buyer's remorse is easy. Get a refund, or earn more money. What about seller's remorse, hm? Namely:

-A tiki of significant cultural value which I parted with on the grounds that it was made out of bone (really, 12 year olds shouldn't be allowed to decide this sort of thing)
-A very, very valuable antique globe ($7? Sure!)

and more recently:
-My entire Travis/Coldplay discography (WHY? WHY?)
-Various fossils and ephemera (I can't afford to ship rocks to America)
-My bicycle and my Sega Master System 2 (I haven't sold these yet, but I'm going to have to, and it's going to suck)

I wander around my living room, picking up things and chanting; I don't need this

Okay, folks. Your turn! Any stories of going back to the school gala to retrieve your bravely-donated ponies and teddies?