itt we post sick burns that have not yet found a target, in the hopes that they will one day be judiciously deployed in the service of mankind "that guy is like ellie kemper doing an impression of a man"
"I was going to say how much you've let me down, but I don't want to sound like your father/mother*" * As appropriate
"Your opinion/avatar AND/OR taste in movies,music, video games is more rancid than a repugnant strumpet's second hand underwear that was received as a gift from a anthrax coated, swine flu infested leper that attended a Coldplay concert who thought they were paying to see Nickelback." Or for something more succinct when a quick draw is required, "American, eh?"
After traumatic experiences of bullying, closure is important. A useful tip for achieving said state of catharsis is not to keep reminding everyone of the event in question. Hmm?