I know the waxes, details sprays, and other things are supposed to make the surface of the car more hydrophobic, and let water bead up on it. Mine stays well waxed, and I love the way water had trouble sticking to it. However, what I want to know, is how to make my car this hydrophobic!
YouTube - Bouncing Water Droplet Falling onto Super-Hydrophobic Surface
Although, I am a bit scared that if my paint was that hydrophobic, the water in the radiator may be rush out of the bottom of the car.