In this video, a shirtless inventor explains how he made a cell-phone activated stun gun to administer a shock to bike thieves.
Bike thieves suck, so I decided to get even. Why not track and, if you'd like, shock these most egregious of folk?
With a $40 pay-as-you-go cell phone, stun gun, and some basic electronic components, you can teach bike thieves a lesson and, hopefully, foster a small social change through individual action:)
How to end bike theft (Instructables)