Try to figure out how high a stack of quarters is by just eyeballing it. It's a guessing game that fools them all! Bonus trick: how many drops of water can you fit on a nickel? This week we've got two ingeniously simple scams, both of which take advantage of awesome and strange gaps in our perception: For the first one, stack 10 quarters and place them on some kind of pedestal (like your cell phone). Then in front of them on the table, place (in order) a 50-cent piece, a quarter, a nickel, a penny, and a dime. Ask your mark which coin, when placed on its side, will be as tall as the stack of quarters. For your next scam, grab the nickel from scam #1 and ask them "how many drops of water can I place on this nickel before the water overflows?"