Many inventions are disclosed. Some aspects are directed to MEMS, and/or methods for use with and/or for fabricating MEMS, that supply, store, and/or trap charge on a mechanical structure disposed in a chamber. Various structures may be disposed in the chamber and employed in supplying, storing and/or trapping charge on the mechanical structure. In some aspects, a breakable link, a thermionic electron source and/or a movable mechanical structure are employed. The breakable link may comprise a fuse. In one embodiment, the movable mechanical structure is driven to resonate. In some aspects, the electrical charge enables a transducer to convert vibrational energy to electrical energy, which may be used to power circuit(s), device(s) and/or other purpose(s). In some aspects, the electrical charge is employed in changing the resonant frequency of a mechanical structure and/or generating an electrostatic force, which may be repulsive.