Actress Peg Entwistle actually did commit suicide by jumping from the top of the "Hollywood" sign in the hills above Hollywood in 1932. She is being talked about by a Tour Guide while Tod Hackett (William Atherton) and Faye Greener (Karen Black) are on a date.
Karen Black claimed that behind-the-scenes gossip stemming from this production ruined her career. She also said that the seven months she spent making the film were the worst working experience of her life.
The song, Dancing on a Dime, is a reference to so-called "taxi dancers". These were women who worked in public ballrooms where single men could come to dance with them. The men would buy a number of paper tickets from a cashier who dispensed them from a roll at the door for the price of 10¢ apiece. The men would give the dancer a ticket at the rate of one per dance, for which they would earn a few pennies' commission. This was the subject of the Barbara Stanwyck film Dix sous la danse (1931).
Using diffusion filters and camera angles that often let sunlight deflect off of characters and objects within the frame, this film is considered by some one of the most uniquely photographed of the 1970s, and Conrad L. Hall received one of its two Oscar nominations, his for Best Cinematography.
The name of Donald Sutherland's character is "Homer Simpson", which is also a lead character name in Les Simpson (1989) and its spin-offs. Apparently the naming is purely a coincidence, as the cartoon character was named after real people that cartoonist Matt Groening knew. As a gag, Sutherland voiced a guest character in Lisa the Iconoclast (1996) who meets the more famous Homer Simpson.