Don't Break the Bottle is designed to exasperate your guests, making them work for their opportunity to imbibe. It fits on any standard wine bottle, and nobody drinks until that puzzle is solved, one way or another.
Please, don't invite me to any parties where I must somehow solve a puzzle to get to the precious wine. Only the most sadistic hosts would do such a thing. Maybe this puzzle's alternate purpose would be to serve as a sobriety test, to be placed on bottle number three...?
Don't Break the Bottle: sobering parties everywhere [Sci Fi Tech]