Researchers have made a fabric, made from polyester fibres which is coated with millions of small silicone filaments. This the most water-resistant clothing which was ever created by man.

Because of the nanometre-scaled filaments, a coating which stops water particules from going through the coating to the polyester fibres which are underneath. This mixture between a hydrophobic surface and a nanostructure coating leads to a super-hydrophobic effect.

This is similar to the surface of Lotus leaves. There are many applications for this: from stain resistant clothing (see video) to reducing water drag in submarines or swimmers. This could lead in a drag decrease of up to 20%.
Here's a little video from the Today Show with a stain resistant shirt which usese nano-technology (Nano-Tex material).