No one can deny that toys can hold a special place in people's hearts. Electronic toys can be even more alluring by their ability to come to life through light, sound an motion. Though there is great value to electronically generated and programmed dynamic behaviors, when toys require batteries they can be both annoying to use and wasteful. Play is, by its very nature. an activity that includes physical motion, so why not harness that motion to use as the energy that powers the plaything itself?