RIP ICQ. I still have logs of chats from highscool. It was really my first foray into the idea of chat. I remember that I once did a presentation for a linguistics class on the use of emoji and the various shorthands that showed up in chat and people were actually interested because it was so new(1).

(1) Yes IRC far predated ICQ but the linguistic norms there differed significantly from ICQ, it was all in my presentation, you had to be there :)