Very Low Power Sensors

Could revolutionize sensing, since power is such a big constraint:

A 30 picowatt sensor ... It only consumes 30 picowatts in sleep mode, which means that a simple watch battery could power the chip for more than 200 years. Of course, this is not a processor for your next computer. It is designed for sensor-based devices such as medical implants, environment monitors or surveillance .... "

A correspondent writes: One application, the i-button.