[sytelus]

As always, my question for all miniature cool looking devices is just this: How do you power this thing?

[BenoitP]

I think it would be just like RFIDs and NFCs: you send power to the antenna, the chip uses it to make a measurement, and to send it back.

Maybe it can take enough energy from the ambient RFs. Maybe we will see a lot of people bringing their phones close to their faces from time to time, and people would be confused. "What are you doing with your phone, do you have an ear in your eye?"