Probably one of the strongest effects and ‘bar bets’ that you can find. All that see it just rub their eyes in disbelief afterwards. You borrow a regular beer or glass soda bottle and a ordinary quarter. You then push the quarter through the bottom of the bottle and everyone can see it now inside! You can show the quarter in the bottle briefly then pour it right back out. Upon examination, they notice that the coin is too large to fit in the opening at the top!