CDBot (I know, I couldn't think of a better name) is an autonomous mobile robot built around a few old CD ROMS (AOL etc!). It's sensors include 2 LDRs for light following, 3 bump switches, 2 IR proximity detectors, 3 IR reflective sensors for line following, 1 pyroelectric sensor for people detection and 1 Sharp IR range finder. The brains behind the robot (loosely speaking, anyway) is a Motorola HC11 microcontroller and the robot is driven by 2 modified servo motors. More details can be found at http://www.botic.com/users/angus Email: angus@ukmax.com