To prevent car accidents, Steve Gardner started working on a lighting system. The vehicle maintenance supervisor for the Lucas County (Ohio) Board of Developmental Disabilities, Gardner invented a system to increase visibility of the bus and young pedestrians. Two red LED lights mounted on a bus's front grille raise its visibility, and a white LED floodlight attached to the front bumper illuminate children crossing the street. Unity School Bus Parts of Marine City, Mich., is marketing and distributing the system for about $225, or about $120 for the white LE...