Apparently a woman found a million dollar painting in the trash on the curb.
Another woman found an old cello lying in the trash, took it home, and asked her boyfriend to either repair it or turn it into a funky CD rack. However, before he got around to it, she saw a news report and was dumbfounded to discover that it was in fact a priceless stolen Stradivarius.
This is my favorite. They didn’t even buy the thing - it was lying around in their attic, put there by some previous resident of the house. And it really looked like nothing, maybe part of a vase or something.