"Do you remember three dimensional chess? I never tried it, and don't know if it's still around, but it got me to thinking. What if a board kept expanding? Instead of 8x8 it became 9x9? A couple of pawns could arbitrarily be added every time the board got bigger. Maybe at 10x10 a bishop or a knight would appear. What if instead of ending the game the objective was to just keep playing the game?"