Man, the postal system is suh-weet! You’ll be thinking that too after checking out this map! Click on the map and type in a zip code, and as you enter more digits it will highlight all the zip codes that begin with the numbers you typed. It’s a lot of fun!
For more country-quantizing fun, check out the numbering system for the US Interstate Highway System. If you’ve never thought about how the highways are numbered, it should all make sense now. And it’s far more interesting than the Department of Transportation’s super lame attempt at making the Interstates seem cool!