Silly bar tricks are only silly when you're not using them to get free drinks or make a buck, but once you start adding tricks to your repertoire that actually pay off they go from silly to super useful.
Some bar tricks require tricky wording or drunk victims, but this trick simply requires you to think outside the box- and figure out how to make a four straw crosshair into a square by moving only one straw.
This trick is a one-time only deal, but imagine the joy you'll be bringing to others when you teach them a simple way to score a drink without actually tricking or conning anyone!
-Via Rare