When he was a boy, John Weber, 70, was given an old cup by his grandfather. He assumed that it was just a worthless piece of brass and occasionally used it for target practice with his air rifle. Eventually, Weber decided to have it appraised, and experts concluded that it was a 2,300-year old Persian gold cup of enormous value. It sold at auction for £50,000 in 2008.

Link via Say Uncle | Photo: Duke's Auctions