At 91 minutes, Marty was the shortest film to win an Academy Award Best Picture. Gone With the Wind is the longest, at 238 minutes. Yup. You could fit 2 ½ Martys in one Gone With The Wind. (Source)

Author Don Delillo grew up in the Bronx amid Marty's stomping grounds, and set his novel Underworld there. Delillo said in an interview: "I was very young when I saw Marty by Delbert Mann, which takes place where I used to live, in the Italian part of the Bronx. The film was shown in Manhattan, so there were eight of us guys, packed in a car to go and watch it. The opening scene takes place in Arthur Avenue. It was our place! Seeing our street, the shops we patronized, there in a movie theater, that was amazing. It was as if our very existence was acknowledged. We never would have thought that somebody would make a film in those streets." (Source)

At the time Ernest Borgnine was shooting Marty, he was best known for playing a character who murdered Frank Sinatra's character in From Here to Eternity. The locals were die-hard Frank Sinatra fans (an Italian boy who'd made good) and threatened him until he explained (in fluent Italian, natch) that the two were good buds. (Source)

Things didn't end as happily for Marty composer Roy Webb as they did for the film's characters: In 1965 lighting struck his home and he lost every piece of music he ever wrote. Webb retired immediately after. (Source)