The anxiety and suspense involved in staring as you see a friend is typing an instant message or facebook chat message but never seems to complete it. The feeling can last for minutes or even hours. Unfortunately unlike actual blue balls, chat blue balls can not be relieved by jerking off.
Person 1: "What's with Freddy, he was supposed to come out with us an hour ago?"
Person 2: "He looked pretty pissed, he's probably suffering from chat blue balls again."
The angst and sexual urge you feel when chatting with someone online and you really just want to see them in person instead. Like actual blue balls, this can be temporarily relieved by jerking off, but is only truly resolved by visiting the person of desire.
Don't type so dirty like that, it's giving me chat blue balls again.