It seems that we've come to a point where many families have as many cars as they have drivers - heck, I know lots of people who have more cars than drivers. In spite of that trend, there are families who manage to survive, or even thrive, with only one car. If you are used to having two cars, having one car can be an adjustment, but it often presents as many benefits as handicaps.
Why might you be trying the one-car lifestyle? Maybe you're moving and one car is in transit, maybe one car is in the shop, maybe parking is scarce and annoying. Or maybe you hope to cut back one of your family's biggest expenses by eliminating the extra registration, insurance, maintenance and other costs of a second car. (I didn't include gas because sometimes eliminating a car can use just as much gas - it all depends.)
My family has lived with one car a couple of times, usually for a number of months but once for several years. When we moved to Hawaii, we brought my old Honda and did not purchase a second car for nearly two years. It was made a lot easier because we didn't have children and Hawaii has an excellent bus system. We quickly learned that cooperation and communication were key to making it work, and we did get a cell phone (this was back before they were quite as common as they are now.) Looking back, it doesn't seem hard, despite the fact that we lived a half-hour from pretty much everything.
Since then, we went single car for a longish stretch when we moved overseas, and then again coming back. I would love to go back to having just a one car again and have hopes that we might be able to do it next time we move. I'm trying to acclimate our family to walking and riding bikes as much as possible, despite living in a very car-centric suburb of DC with virtually no public transportation.
All of this is a very long introduction to a great article at Five Cent Nickel, Testimony of a One Car Couple. In this post, Matt doesn't advocate giving up your extra cars but rather tells of his family's experience during an unplanned adventure into one-car-land. The comments provide even more insight into the possibilities of surviving with just one vehicle.
Having only one car isn't a good choice for everyone, but it is an option that some families might want to consider. It requires effort but the rewards might be worth it!