Borrow a coin. Get it signed and bend it in your hand. It is a clear and strong effect. Titanas explains two different variations which can be performed standing.
The video is shot for my taste from a bit too far, particularly in the demonstration part the coin is hard to see. However, the explanation is clear and should not cause any difficulties for you to learn this wonderful effect.
1st edition 2008; duration 8 minutes 13 seconds.