A research partnership between Carnegie Mellon University and Microsoft has produced a novel method of physical interaction targeted at mobile devices that uses skin as an input interface. This input method, known as "Skinput," measures the generated by tapping on your body.
The current prototype device captures input using a band around the upper arm, a form-factor that's ideal for controlling mobile devices, even when walking or running. One possible application is a method for controlling an iPod (mounted via an arm-band) with skin-touch-based input to select music tracks while jogging. In other words, your arm can become an iPod remote!
The Skinput researchers seemed to have focused on improving Skinput's accuracy and discarding erroneous or extraneous touch input that would otherwise cause problems. This may be similar in principle to the type of "palm detection" featured on Apple multi-touch trackpads; it's a means of differentiating true gestural input from noise data.
While Skinput itself is an interesting input method, combining it with a display opens the door to many more possibilities. In one demo, the researchers mounted a pico projector on the touch-sensing armband to project a graphical interface (e.g. buttons) on the user's arm. Another demo turns the fingers into a controller for a game of Tertris. See the above video for more.
Will your next phone respond to skin touch rather than "clunky" buttons and touchscreens? It seems like Carnegie Mellon University and Microsoft have big plans, and maybe you will end up dialing your Windows Phone 8 Series with your arm.