Thank you nanotechnology for bringing us the windows that clean themselves.
Pilkington Activ Self-Cleaning Glass is coated in a chemical layer that reacts with ultra-violet rays from daylight to disintegrate organic dirt. Then when rain or water hits the glass, it simply takes the dirt with it.
The substances in the glass are normal household chemicals, and the huge reduction in spray-and-wipe cleaning supplies adds up to a greener window.
The FAQ page states that the glass is designed to reduce the amount of maintenance required. I guess it means that we'll still have to clean it when the weather is dry or when the window is extra dirty.
Via Treehugger.