Four undergraduate students at UC Berkeley created a rocking chair called the Volta that stores kinetic energy from an attached pendulum.
At first, the team thought such a chair would be a novelty, a student project that had rocking chair users see how much energy they could generate from rocking back and forth.
Of course, once chair sitters interacted with the smartphone app that tracked the energy they were producing, they wanted a USB port to keep their iPhone charged up.
