I read this thread and laughed at the hypocrisy. People want others to give stuff up, but don't want to do it themselves. Of course, one person giving up a car isn't going to do much, but if those losers are going to preach it, they should follow suit.
I gave up my car after the first year of living in Chicago. Definitely not for a noble purpose though. I work from home if not traveling, so I was paying for a garage and wasting money. Bus stops right in front of my apartment, and the el is down the street. If I need a car, I'll rent one.