A rain sensor, particularly for a motor vehicle, includes a light-conducting member arranged in an intermediate layer of a glass, and is designed as an optically closed system. The sensor includes a sample chamber to hold a sample in electrolytic contact with a working electrode, and in at least some instances, the sensor also contains a non-leachable or a diffusible second electron transfer agent. In another embodiment, the shaft comprises generally rigid material, and the region comprises a flexible joint between the shaft and the head. If the conditional actuation device is not used, a continuous actuation device may be connected to the luminaire. Likewise, upon a player move, at least one game chip is converted to a player chip. Metal or metal silicide can also be used.