Bob Davis scored a complete power supply including a 5 KV transformer, 100 uf Capacitor and a contactor on eBay for $100 and did what any sane person would do—he built a can crusher.

The first test was caught on tape, and despite issues with a broken meter, the device managed to crush the hell out of that soda can. In fact, it was so powerful that the power transformer shorted out and the diode was "blown to bits". Interesting, but not quite as manly as it could be. I'm waiting to see someone build a crusher that smashes a can flat on a dummy's skull. [Bob Davis via Gadget Lab]