Play the Marienbad Game.
Make sure Contextual Alternates are on. In InDesign, turn on the World-Ready Composer. Type the word MARIENBAD (all caps), followed by a vertical bar (German keyboards: Opt-7 Mac, AltGr-< Windows), and a Marienbad game setup will appear: 4 rows (A, B, C, D) with 1, 3, 5 and 7 items. Now the players take turn, taking away any number of items, but from only one of the rows each time. To do so, each player types the letter for the row (A, B, C, D), then the number of items he or she wants to remove from that row (1–7), and confirms the move with a vertical bar. The game goes on until one player is left with the last item and loses.