iPhones? Wii’s? Bet you think those are pretty fancy, right? Well, when it comes to sheer wow factor, those technologies have little on Skinput, which lets you control things by simply pressing different parts of your skin. Your skin! The system, which was developed by researchers from Carnegie Mellon and Microsoft, turns the human body into an interface. But rather than using electrical impulses, which is how the iPhone and other touch screens work, it actually measures the movement of sound made by tapping different parts of the arm or hand. But in addition to measuring acoustic waves, the…