This is the result of a large capacitor being discharged into a small wire. The capacitor bank is rated 3000uF, and is charged to 1200VDC via a Microwave Oven Transformer based power supply made by Aron. The capacitor is charged up, and is then shorted into a small piece of #22 magnet wire via a spark gap. The result is a powerful flash of green light (from the vaporized copper), a *thump* of sound wave pressure, and a 4' diameter cloud of smoke. Plain white printer paper was placed directly on top of the wire, so that the out-flying particles are imbedded into the paper. The resulting pattern is what you see here.