I did this, but the I spy version. When it claimed that it was looking at something in its environment I questioned if it could really have an environment, being a program. It conceded this point and told me it'd select something from its database. After that I guessed CPU anyway and it told me I was correct.

I just tried 20 Questions with ChatGTP-3. It failed miserably. It would occasionally get too fixated on unnecessary details of an animal, especially canines and felines. It even started guessing the animal early without knowing enough. I had to keep reminding it to ask broader questions to narrow down the answer. Only then did it ask simple questions like, "Does the animal primarily live on land?" I even had it summarize what it knew so far, 2 or 3 times. The questions weren't great when compared to playing with young kids.

The answer was platypus. It was at 55 questions before I gave up. Maybe ChatGTP-4 would do better.