Charlie on the M.T.A.
The iconic character from the beloved song "M.T.A." (known as "Charlie on the M.T.A.") boarded the Kendall Square station on what's known today as the Red Line.
In the song, he transferred to the #39 streetcar to Jamaica Plain (now replaced by both the E line trolley to Heath Street and the #39 bus to Forest Hills) and then remained trapped in the system because he did not have a nickel to pay the exit fee.
(Is it too late to ask why Charlie's wife, who thoughtfully passed a sandwich to him every day as the train rumbled through the old Scollay Square station, never chose to give him money?) The song became so entrenched in local pop culture that the Charlie Card and Ticket portray him riding the Green Line.