The one my guests seem to like the most is this one.

Take 5 toothpicks and snap them in half without actually breaking them apart (meaning leave a joint in the middle of each match)  A Joint? What kind of bar is this?.

Arrange them like this.

Tell your audience to turn the toothpicks into a star without physically touching them.

When they can't figure it out dip a straw into the nearest drink and cover the end of it (the way most bartenders taste the drinks they make) and put a drop of liquid on the joint of each toothpick. Watch it slowly close into a star.

Dan