First, let's accept that New York City is a dirty place. Any city with 8.4 million people living in close quarters is going to get a little messy. So every now and again, you have to clean the streets. On average, about two days per week. So how do you run a street sweeper up and down the streets when the curbs are literally jammed with cars? Answer: You force them to move. Practically at gunpoint.
If you drive a car in New York, the street you park on has a sign like the one at right. And for an hour and half twice a week, you have to be with you car if you want to hang on to your parking space. The dance goes something like this:
Let's say you're parking next to this sign, that says "opposite street parking Mondays and Thursdays 9 am to 10:30 am." At 9 a.m. Monday, you either leave with your car or you move it and double-park on the opposite side of the street. But you can't just leave it there. You have to stay in the driver's seat with the engine running in case someone needs to get out or in case the NYPD traffic officer (who travels just ahead of the street sweepers) needs you to move.
Forget to be there at the designated day and time? Guess what. You win a great big parking ticket courtesy of the city of New York. Theoretically, you could get towed, but the odds are the sweeper will just work around you and your several-hundred-dollars-poorer butt.
Here's the fun part: Even after the sweeper comes, you can't leave. You have to stay either in your car, or within arms-reach for the entire hour and a half. So for a total of three hours each week, you'll see otherwise productive New Yorkers sitting in their idling cars down entire miles of streets, running the air conditioning and reading the latest Amy Tan novel. Imagine how many diseases might be cured or ad campaigns created if everyone with a car in this city didn't waste their time twice a week waiting to move their vehicles!
This is the craziest dance I've ever seen. And I still remember my clumsy friend Wilmer trying to learn how to Alaman Left in junior high square dancing class.