Kids Halloween Candy Code
http://www.cockeyed.com/archive/candy_code/candy_code.html
"Growing up in the Bowling Green neighborhood of Sacramento, I was taught how to read and mark houses with the Halloween Candy Code. For kids with an early curfew these codes were invaluable. Once we tagged a house, our peers could use our marks to reap the best full-size chocolate bars while avoiding Chex mix and dried apricots."