Although shooting a stream of plasma into your mouth sounds painful, the blowtorch actually works in small pulses, which lets the flame's gasses ionize and cool down a little before they can burn you. So far, dentists have only used this technology to sterilize teeth during root canals, but have a few other ideas on where else to use it—perhaps, in the future, zapping away diseases on your genitals? [R and D via PopSci]