A few years ago, while searching for something strong enough to coat headers with, we came upon ceramic coating. Ceramic coating is a coating using ceramic (imagine that), it can resist temperatures up to 1800º F. Ceramic coating also insulates your headers eliminating heat in your engine and engine compartment. Not only is this stuff heat resistant, it can take a pretty good beating too. Ceramic coated objects that aren’t too big can also be polished (not quite chrome, but pretty darn close).
Ceramic coats are available in many different colors:
Putting a clear ceramic coat over your powdercoated things can improve their durability and chemical resistance (great for motorcycle fuel tanks).