Two runners I knew would taunt and yell at each other at the end of races (and sometimes during them). The animosity kept building until after a local 5k one accused the other of cutting the course, resulting in the winner and second place finisher getting into a full-on scrawny-nerd brawl. That alone is pretty hilarious, but it was a Girl Scout fundraiser fun run so it played out in front of a bunch of elementary school girls and their moms.