Why oh why 1) aren't cabbies required to demonstrate a basic working knowledge of Boston/Brookline/Cambridge/Somerville/Newton, or failing that, 2) isn't every cab equipped with a GPS?
The only cab company I've consistently been happy with is Veterans Taxi in Newton. They're dependable, polite, reliably take credit cards and each cab has a GPS, in sight of the passenger.
(Well, there was that one time the driver was listening to conservative talk radio, and the host said that nobody had ever died from a lack of access to health care, but the transportation itself was fine.)
Sometime when I'm at a computer, maybe I'll post my recent Bay State Cab experience. It was not a positive one.