The Fun Theory

How to make people dry their hands using the hand dryer instead of paper towels? When someone move his/her hands above the hand dryer it turns on and at the same time the kaleidoscope. The person will see the kaleidoscope moving only when the hand dryer is turned on. Different kaleidoscopes should be installed in different places thus people will be interested every time they need to dry their hands.
Submitted by Virgínia Amorim