Tic-tac-toe (or “Noughts and Crosses”) is a game simple enough to implement in any computer system: indeed it’s often used in beginner’s programming courses. A more challenging project ...

Discover Games Summary Academy: Tic-Tac-Toe is a tic-tac-toe game for DSiWare that features 4 variants on the classic game.

So tic-tac-toe falls into the sad category of solved games. Challenging someone to recite the alphabet backwards would be more unpredictable.