I forgot where I got this from. All I do know that this is a perfect lead in to a regular torn and restored napkin trick. Seriously. You start with this one which has a cute sucker element to it and continue with the standard trick which also has a sucker element. If you go on doing the additional phase of the spectator being involved this, with the right jokes could end up a complete stage piece.
So any credits I will add, if you give me feedback on this.