Abstract: An optical switch for controlling an operative condition of a headset. The headset includes a microphone boom that is rotatable with respect to a housing for the headset. A rotator element is coupled to the microphone boom such that the rotator element rotates with respect the housing along with the microphone boom. Selected portions of a surface of the rotator element are conditioned to be more reflective than the remaining portions. Alternately, portions of the rotator element are opaque. A pair of optical transceivers are in fixed positions relative to the housing. When the microphone boom is positioned approximately straight upward with respect to a user's head, reflective portions of the rotator element are within a field of view of each optical transceiver of the pair. In this position, the headset is in an "off" or "standby" mode.

Abstract: An automotive anti-theft system comprising an enclosure of a device or system necessary to operate the vehicle; this enclosure also enclosing an interlock or disabling entity disabling operation of that device or system, and also enclosing a decoder controlling that interlock. The enclosure is substantially resistant to penetration, unauthorized removal and destruction, and is secured to the engine of the vehicle by special fasteners that can be easily removed only by using special custom tools, and or by fasteners having non-polygonic off-center bolt heads and or non-polygonic non-circular bolt heads, these fasteners being surrounded by a spinning collar that is journaled onto the shaft of each bolt.