Perhaps you saw the first episode of the excellent series "Richard Hammond's Invisible Worlds" on Win TV Tuesday night at 9:00PM following TopGear. You should make an effort to catch the next two episodes. Episode two will be on Tuesday 23/11/10. In the third episode (Nov 30th probably) Hammond has a short story on work being done by NASA to make space-gear dust repellent. The research is based on understanding the microscopic properties of the Lotus leaf. General Electric are also doing similar research.
What you will see in "Invisible Worlds" is a surface coating developed by NASA, from this research, that can make any surface as water repellent as a Lotus leaf. Sometime soon there could be a product that makes any item of clothing hydrophobic. Any lightweight fabric could be used to make a backpack, tent, coat, shirt, trousers that simply can't get wet and is entirely self cleaning because dirt won't stick to it either.