Not bike related, but two years ago I was at a Flea Market just south of Pittsburgh and scored a Rolex Oyster Perpetual that was mixed in a box of other watches and jewelry. I asked "how much"? The guy said..."it probably doesn't work...gimme a dollar an it's yours." I figured it was probably a fake, but for a dollar, why not?
A quick cleaning and it looked too good to be fake. Hours of research on the 'net convinced me it was real and finally a jeweler confirmed that it is.
Now if I can just find a $10.00 Colnago at the Goodwill store...