Here in Canada our postal code tells you what street you're on plus whether it's an even or odd number (i.e. which side of the street). But I guess when you use three letters and three characters you can have a lot more granularity.
Wow. Every now and again you come across examples of a bureaucracy coming up with a neat and elegant solution to a problem. Doesn't happen often mind, but I think we should celebrate it when it does.
I hope the designer of the Canadian postcode system is a national hero.