From Victor Bogado da Silva Lins’ letter in Bruce Schneier’s Crypto-Gram (15 May 2004):
You mentioned in your last crypto-gram newsletter about a cover that makes a license plate impossible to read from certain angles. Brazilian people have thought in another low-tech solution for the same “problem”, they simply tie some ribbons to the plate or the car itself; when the car is running (speeding) the ribbons fly and get in front of the plate making it difficult to read the plate.