Leave this wallet lying around to test the honesty of your victims.
Set the bait with some currency (fake or otherwise) sticking out.
When opened, the exploding wallet fires a loud cap.

Requires caps.

Your victim's good luck at finding a wallet on the ground changes quickly to shock when the wallet explodes with a loud bang. Leave the loaded wallet on the ground in a busy place and it won't be long before somebody picks it up. If they don't open it right away, approach them and explain that you think it's your wallet, would they check the ID inside. After the cap explodes and the wallet flies out of their hands, you
can reload it and annoy the next chump that picks it up.

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