Ah, I see someone has done bluing; I'd wondered if anyone had done that to a bike. I've done a little cold-bluing and find it difficult to get uniform results, even over small areas, but it looks great when it works. Utmost care needed to avoid contaminating the surface during and after cleaning.

Has anyone flocked a bike frame? I knew a guy who had that done to the tank and fenders of a motorcycle he was building for show. Comes in all colors, looks like velvet, and is incredibly tough. The area you wish to have covered is glued, then the fibers are applied electrostatically.