I saw something on TV tonight about a "car club" where people can go online to rent cars that are parked around their neighborhoods, drive them for an hour or so to do their shopping, then drop them off again. They reckon that people who don't drive much (<6,000 miles/year) can save upwards of £3,000 if they use the car club rather than owning their own car.
Just from my own experience, I've never had a driving license, and finding transportation is the biggest hassle in my life. If you don't drive you can be severely limited with regard to where you can work, where you can live, and what you can do. I've managed to survive up to this point by living in cities or near my work, and by depending on the kindness of my friends and family (which I hate). I lived in Prague for a while, and the extensive network of subway, tram, and buses was absolute heaven. By contrast, when I lived in California, there was a period of a few months where I had to have someone drive me to a bus stop at 7am, ride a bus for an hour, wait, catch another bus, then walk 4 miles to get to work. I'd arrive around 10. If I had been able to drive myself, it would have taken about 30 minutes. But now that I live in rural England, it's worth it to hunker down and get my license, then get a car. I know there's congestion and it's bad for the environment, but I'm really looking forward to having a bit of freedom from the tyranny of bus schedules, and to not wearing out my shoes so quickly.