If you still read automotive magazines it's quite likely you've seen adverts for new-fangled sprays that claim to prevent traffic tickets. They work by over-exposing the flash from a red light or speeding camera and thereby prevent you from getting caught. We’ve never tried them, but this news report features a police officer admitting that they can defeat current speed cameras. The report also has 2 plates that sit in front of your license plate and blocks detection using either a prism or silver sparkles. Both are on the market right now and present some serious ethical issues. We've never agreed with speed or red-light cameras, but this seems like a sneaky way to get around them. Have you ever used such a product? How did it fare?