Blendo was a robot made by Adam Savage and Jamie Hyneman to compete in Robot Wars before MythBusters. Its “weapon” was a horizontal flywheel. After two matches, they were given a newly-created award of co-champion on the condition that they did not participate in any more matches.
The sheer amount of energy stored in and dumped from the flywheel obliterated their competition and posed a very real human safety risk.