When you are playing an online game or watching a video online, and suddenly the action gets herky-jerky instead of smooth, because the server on the other end has slowed down for some reason.
1. I was playing a game, had a damn good game going, and then encountered a server fart which caused me to crash and die.
2. I just encountered a server fart while watching my favorite video...how dare all those other users out there create server traffuck when I want to watch?