Robot-sumo is a sport (yes, Wikipedia got it right) in which two robots attempt to push each other out of a circle (in a similar fashion to the sport of sumo). If I’m not really into Sumo wrestling, I’m definitely into robots (like this Real Life-Size Wall-E Robot), more specifically into sumobots.
I’ve seen some battles, with robots weighing up to 125 pounds, built from scratch or from Lego components. If you’ve never seen them in action, Robert McGregor carefully edited takes from several years of footage and here’s the video!