I just stumbled on this interesting and wide-ranging article on Boston's Mattapan line 1944/45 PCC trolleys. Mention is also made of Philadelphia and San Francisco's historic trolleys:
http://commonwealthmagazine.org recent article on Mattapan's PCC cars
Awesome moment: they still have cords you can pull to stop the car at your stop. (Memories of childhood for sure.)
Tomlinson Run Railroad