University of Illinois nano scientist John Rogers developed a method to print ultra-thin silicon circuits, like those on a computer chip, onto a highly-elastic surface that you can stick on your skin. Think of a temporary tattoo containing electronic components that are one-fifth the thickness of human hair. The possible uses of this are broad, ranging from a tiny patch that will detect when you need more sunscreen and alert you, to implantable (yes implantable) sensors that keep a constant vigil for infections inside the body. Rogers spun out a company called MC10 to commercialize the technology and has already partnered with Reebok on a forthcoming wearable device to track athletic performance.
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