My grandfather worked in NYC for over 20 years and he commuted by train. During those commutes, he sat next to the same man, twice a day - on the way there and on the way back - for years, and only once in at least a decade did they ever speak to each other. "Are you finished reading that?" Those were the 5 words that man spoke to my grandfather, who handed him the paper he had finished reading, and they never exchanged another word again. I don't think they ever even looked at each other.

Best friend he ever had. They still never talk sometimes.