It's basically a riddle game. So I give out a riddle, and people ask me questions to solve it.
So for instance, the one I'll be kicking off the thread with is
A person pushes a boat up to a hotel. He hands the hotel owner money, and pushes the boat away. What's going on in this scenario?
People can ask me yes/no questions, which I'll reply to. If they feel they can guess what's going on, they can guess, and I will say yes or no to that answer. The person who solved the riddle gets to post the next one. Riddles can also be more conventional ones, like the poems that point to an object or something.
How bout it?