These are a couple videos of a FANUC M-2 iA 3S Delta robotic arm that was modified by mechanical engineering student Christian Schürch to continuously remove track sections from behind a toy train and add them to the front so the train can travel around its little circle without falling off. Pretty clever. Also, probably the most practical use for a robotic arm that I've ever seen. "What about building cars?" Do those cars fly? "No." I think you have your answer.
Keep going for a ten minute video, a one minute video, and a view from track level.
Thanks to Carmen, who wants to know if that train thinks it's actually going somewhere or if it realizes it's just chugging around in circles. LIFE.