Water Droplet Bouncing on a Superhydrophobic Carbon Nanotube Array (video)

Saw this the other day, it's excellent. Very easy to take surface tension, hydrophobia and other properties for granted when you see them in a common setting (eg, water dispersing in the dirt, soaking into cloth).

Take the properties to their extreme and you get what are essentially unseen behaviours (outside of research), like this. This video really left me in awe.