I had an odd surge of nostalgia a few years back and reinstalled Gmod to play some TTT. I remember making some 8-9 year old (assuming as much based sound of voice and general lack of ability to coherently string sentences together in English) who filled voice comms with just inane, rambling nonsense sperg out on demand just by cutting in occasionally and going "Nobody cares," or "Shut up". He would constantly fire back with "Nobody cares ABOUT YOUR LIFE!!!" in response to the former. Made for a pretty good laugh. IIRC someone eventually alerted a mod/admin to join the server who warned the kid, and then promptly gagged him from VC when he wouldn't stop. Fun times.
Long, long before that, maybe back in 2010-2011ish, I was playing on one of those dedicated mariokart TF2 servers and I made another kid have a crying fit and then ragequit by constantly running up to him and smacking him with a melee weapon while we were on the same team. He started crying about how he had a "rival" on the enemy team that I wasn't letting him fight by hanging around and smacking him, and that I "didn't understand what it meant to have a rival" until he finally just left the server. That one stuck with me because of just how downright weird that reaction and those pleas were.
Kinda wish I remembered anything more than that.