In this scene cut from the original theatrical release of Saturday Night Fever (1977), watch John Travolta do the Robot to the song "Disco Duck." Our family went to this movie when it was first in theaters but the moment the stripper appeared, my father whisked us right out. (I was 7.) Later, it was re-released as a PG version and not only did we get to see the whole incredible movie but afterward my dad took me to Record Theater to buy the soundtrack on LP. I still have it.
The second scene in the above video is the full "Night Fever" sequence that was edited down in the original cut.