It was June. I was a little broke. And my Mercedes SUV, that I'd purchased when I was single, young and foolish, got a flat tire. The tires were ready to be replaced anyway, and there was no "patching." It was dead.

That wasn't all that was wrong; I'd done a mental list of nits and major issues (like, the front windows wouldn't go up or down; the windshield was leaking; the rest of the tires were pretty shot) that added up to between $1500 and $3500, depending on how far I wanted to go. Really, it was $1000 to get the car in working order again.

I had two children, ages four and one. My house was within a few blocks of three bus lines. The whole family had bicycles and we live in a city that values alternative modes of transit. I was starting to really freak out about global warming; would my kids even have wineries nearby by the time they reached the age of consent? The papers said no.

The next day, a friend emailed. "Would anyone like to participate in a car diet?" There were freebies; a bus pass, use of a Flexcar, some goodies for our bike. We handed over our keys a few weeks later in a ceremony, with the mayor and the Channel 8 news crew standing by.