Well, I _did_ call it that when I wrote a programme, sorry, program fom my PET to play it. But it was a pun on the more conventional spelling, "noughts and crosses" AFAICT, Nought = Zero, Naught = Nothing Tic-Tac-Toe is a name I had met even then, but Tit-Tat-Toe I've not come across before. Any etymological connection with Tit for Tat? Philip.