Funny how when people excitedly tell us: “Oh, guess what?”, we immediately reply “What?” instead of, you know, guessing.
Next time, when someone asks you to “guess what”, try taking your time guessing (or even pretend you are thinking) and reply: “Wait, don’t tell me. Lemme guess…” About a minute later, reply “I’m thinking …. I’m thinking ...”
It probably annoys the person as heck, but it’ll be funnier than just saying “what” right away.