Since May 22, and I don't know for how long, I am in San Francisco Bay Area. Met dk379 and other people whom I haven't seen in years. After completing all "official" business for the week I have returned the rental car, and switched back to the mode of transportation that I had 10 years ago -- walking, occasionally riding a bicycle and using the public transit system -- train, light rail, buses. I have finally found out how San Jose side of the Caltrain line looks like, I never was there when I lived in that area, only had to go by train up to Mountain View.
For the last two days I have walked around in San Francisco, and discovered that I remember San Francisco pretty well, and still can walk there for hours -- I get tired a bit easier after years of sitting in the lab in Colorado, but it looks like I have improved compared to yesterday. In Colorado walking is something that can be done as an "exercise" -- the idea of getting somewhere, or even aimlessly wandering on foot is almost laughable, considering dry, often changing weather, and long stretches of roads connecting pieces of the city together.
San Francisco and most of places in Bay Area are compact, so unless you have to get out of the city, car is more of a burden than a convenience, leave alone necessity -- difficult and expensive to park, have to be careful to avoid accidents in a dense traffic, tied to the topology of the one-way streets.