According to a New York Times article from 1983, 'It was Mr. Zinn's feet and legs, in disco boots and jeans, that walked into the camera during the memorable 1977 opening credits for Saturday Night Fever,' to the music of 'Stayin' Alive.'
In Spielberg's E.T.: The Extraterrestrial, the eponymous alien is taken trick-or-treating by his human guardians, hidden under a sheet. As he looks through the eyeholes of his makeshift costume, we see dozens of kids in costume, but one is highlighted especially: A kid dressed as Yoda, wandering down the street. E.T. follows, excitedly saying "Home!!" It’s an adorable moment and a friendly nod from Spielberg to George Lucas.