Scientists have developed a flashlight-like device that uses plasma to quickly sterilize surfaces, including skin. Fortunately the plasma is cool enough not to damage skin. The device is powered by a 12 volt battery (must be custom, because it's too small for a car battery) and it's claimed it will cost less than $100 once in production. Better still, while plasma has been known to be an effective anti-bacterial, nobody's completely sure why.