A quirky bit of the T is the High speed trolley line from Ashmont to Mattapan with 70 year old PCC cars. Intended as a "trolley freeway" now lives on as a link to Ashmont from Mattapan.
The MBTA is very dear to me. The first trains I ever rode as a toddle to teenager were those of the "T" Here is a collection of MBTA Subway and trolley I have found on RP from the 60's thru today.