Effect: You Put your hand over a coin and then you pull it from under the table.
How to do it: I do it a way that you can have someone sign it and you only need one coin.
You ask someone for a coin, you place it on the table and put 3 fingers in front of the coin (So the person watching can not see it) and while talking to them flick the coin into your lap. Then cover the coin with your hand and reach under the table and pull the coin out from under the table.