If we can harness the power of childhood energy, especially those who play jump rope, we could do very well. This concept aims to take that jump roping energy and make it useful. It’s called the E-Rope and can generate power to charge a pair of AA batteries in each handle.
According to the designer, 20 minutes of jumping would fully charge all four AA batteries. Not sure if I believe that, but anything that promotes exercise and gives you charged batteries is a good thing.