Boston is not on the grid system, it follows old street patterns which include cow paths. Everyone drives offensively, so you will not get any sympathy from your fellow drivers. They will treat you like an out of towner and beep when you F-up. You may also find yourself one minute in the city and the next in a neighborhood with no skyline not knowing where you are. Bring GPS.

My suggestion is plan for a lot of time, and get out of town before rush hour. Park in a garage if possible if you are going somewhere as street parking is difficult with all the cars.