PostitGuess.IO is a free 3D multiplayer web guessing game. Based on IRL game "What's in my head/ Guess Who am I?" Each player must choose the name of a character that everyone know. This name will be put on the virtual forehead of a player. The goal of the game is to be the first to discover the character that has been assigned to you and that is marked on the post-it note in your head. Each player can ask a question to the others who can only answer with "Yes" or "No".