There's wearable computing, and then there's wearable computing.

Just last year around this time the company MC10 figured out how to fabricate small networks of sensors built out of flexible circuitry that stick to the skin of the wearer and collect biotelemetry. By sticking a single square of wavy, flexible circuitry someplace on your person you could keep a medical team appraised of certain aspects of your health. The tech curve, as always, moves like a roller coaster gone out of control... in the journal Nature Nanotechnology a research team at the Swiss Federal Institute of Technology improved upon the design and created flexible circuitry tattoos that can store data on-board and dispense drugs in response. The 4cm by 2cm prototypes are a third of a millimeter thick and are externally powered (they don't yet have on board power supplies), and consist of circuitry fabricated out of new flexible nanomaterials. The current prototypes are unique in that they have non-volatile memory built in, implemented in a technology called resistive RAM, which has some remarkable functional properties in and of itself... This latest generation of functional prototypes has much more processing power than those built just a year ago and use less energy. The tradeoff for that added functionality, however, is that power has to be supplied wirelessly from an external unit. The current prototypes are capable of recording and analyzing certain aspects of the wearer's metabolism and can react by delivering drugs under certain conditions. Projected use cases for more advanced versions of the wearable tattoo/computers (at the rate things are going, give it eight months or so) involve recognizing biosignals characteristic of certain conditions (such as seizures) or changes in hormone levels and treating them in near-realtime. It seems reasonable to hypothesize that one of the first improvements will be the addition of on-board power to make them more stand-alone, and I'd be surprised if somebody didn't try to give a model after that a Bluetooth-compatible transceiver chipset so that it could communicate with a hand-held computer or smartphone. This is already being done with insulin pumps so it's not much of a stretch to say that one could be added to a test type biomonitoring applique'. Fitbit users, time to keep a sensor net trained on Amazon's list of new products...