I don’t know about 12 fingers, but I heard a joke once about a 12-inch pianist.
A guy walks into a tavern. As he walked up to the bar he noticed a twelve-inch man playing the piano, so he asked the bartender, “What’s that all about?” The bartender told him he that would tell him later. So the guy asked the bartender for a drink. The bartender said, “Before you get your drink, you get to rub the magic beer bottle and make one wish.” “Okay,” said the guy. He went over to the magic beer bottle and rubbed it. Poof. Out came a genie. The genie, of course, said, “You have one wish.” The guy thought about it and then wished for a million bucks. A cloud of smoke filled the room, and then both the genie and the guy disappeared. In a few minutes, the guy reappeared back in the bar with a million ducks all around him. The guy was astounded and said to the bartender, “Hey! I didn’t want a million ducks.” The bartender replied, “Do you think I wanted a twelve-inch Pianist?”