Freestyle Dancing (1964)
Great footage of some people letting loose and dancing freely at a club in the mid 60's. Some of the women dance like clockwork in perfect little movements. There is an interview near the end where a woman expresses why she enjoys freestyle dancing compared to traditional "upclose" dancing.
This is a clip from an incredible Canadian documentary called "Twist" (1992) which goes through many popular dances of the 60's. It's filled with great footage and insight on how popular dance shifted along with our culture.