Everyone makes mistakes, but when it comes to the U.S. Mint, mistakes are worth thousands. Something as small as a double-stamped year on the 1955 Lincoln Double Die Wheat Cent could fetch $1,400, while a 1981 penny mistakenly printed on a nickel sold at auction for $250,000. Those are a few valuable oversights! Put a down payment on a house, buy a new car, and read on as eBay lists 7 exceptional error coins you might find in the penny jar.