This soft, flexible power generator creates energy when bent, pressed or stretched. In a wristband it can light up several dozen LEDs with the motion of your wrist (10-20 microwatts per cm), and costs less than 1 US dollar to make.

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This soft, flexible power generator creates energy when bent, pressed or stretched. In a wristband it can light up several dozen LEDs with the motion of your wrist (10-20 microwatts per cm), and costs less than 1 US dollar to make.