After a month of bidding, an incredibly rare copy of the NES cartridge Nintendo World Championship 1990 has sold for a price of $21,400, plus $10 for shipping. Listed on online auction site myebid.com (screen capture hosted locally for posterity) in a lot of 24 NES games with an unassuming starting price of $24, the game was sold by a man apparently unaware of its status as the most valuable NES cartridge in existence.