Luigi Catacuzzeno lines up a long, thin needle against a frog egg. Peering at it through a microscope, he turns the knob of a machine to nudge the needle a fraction of a micron forward. Then he deftly punctures the membrane of the soft little egg to wire it to a small capacitor, an electrical component similar to a battery. This unusual arrangement is Catacuzzeno’s attempt to harvest energy from biological cells to power tiny electronics.