For my work experience about 20 years ago I worked at Westland Helicopters and had a Mini. One lunchtime I noticed that the black back bumper on my car had a fleck of paint missing and it was actually a chrome one painted black! My uncle, who was high up in Westland, told me to drop it in with the spray shop there. Anyway... When I picked it up a few days later the guy gave me the bumper back and said "I'm sorry, we didn't have any black paint" ... "But it looks black..."... "No, it's the anti radar paint that we use on the bottom of helicopters, it's £1,500 a litre" lol :-) I never did tempt my luck with a speed camera but I was frequently inclined to try!