I like nano technology. The fact that at some point in the future a cloud of self-replicating, devouring micro-robots will take our bodies apart molecule by molecule is cool, academically speaking. Right now, though, nano technology is used to keep your windshield water-free.
I bow to our futuristic micro overlords and thank them for making my car safe.
Wiperless windshield created, powered by nanotech [Sparking Tech]