There's an article up on Salon about a new book, Traffic. It looks at the psychology behind driving, with some interesting quotes: signaling is revealing your intentions to the enemy.
Maybe, but that assumes you are signalling a wish to change lanes, rather than providing immediate warning of your intent to change lanes regardless of the presence of another vehicle, that being French-style signalling rules. In fact, despite all the claims that Boston is a hard place to drive, it isn't, not by European standards.
What is interesting in Boston is parking. There are parking lots to park in all day, but they are expensive. The alternative is to park where you aren't allowed to, and risk being ticketed. It all comes down to some simple equations. If P(ticketed) is the probability from 0 to 1 of being getting a parking ticket, and that happens one day in five then P(ticketed) = 0.2. If the cost of a ticket, is say , $50, then the daily parking costs are $50 x 0.2, or $10; less than a parking lots' cost of $20. It's cheaper to park illegally and get ticketed sometimes. So the drivers do.
In Bristol, the equation is even simpler. Outside the pay-to-park inner core, P(ticketed) is effectively zero, so the daily cost of parking where you want is 0. Whereas the cost of using a car park isn't, nor is the cost of using FirstBus. So what do people do? They drive close to the centre and park where they seem to be able to park without being ticketed. Because no other action would make sense.