True Math Genius
This trick will bring a smile to the face of even the most hardened math geek. First, lay matches on a table to form the equation I + II + III = IIII (crossed matches make the plus signs and parallel matches make the equals sign). Challenge your opponent to make this statement true by moving only one match and without messing with the sum after the equals sign. The trick is to pick up one match from the II, and lay it across the middle match in the III, making the full equation read:
I + I + I + I =IIII.

Two Glasses II
This time, use shot glasses—fill one with colorful liquor and the other with water. Bet that you can make the liquids in the two glasses trade places without using any additional receptacles including your mouth or other glasses. Here’s the trick: cover the liquor shot glass with a driver’s license or other plastic card and upend it, stacking it face-together with the water shot glass, which sits upright on a table. Gently remove the card—the heavier liquid will flow into the bottom glass, displacing the lighter water into the top glass.

Bottle Cap T
Arrange six bottle caps on the bar in the shape of a T, with four caps vertically and the remaining two caps on either side of the uppermost cap. Bet that by moving only one cap, you can create two lines of four. Like the first bar bet, the trick is thinking three-dimensionally—take the lowest cap and put it on top of the highest, middle cap. Both the horizontal and the vertical line now contain four caps!

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