One of the best uses of pop music in film history, this montage set to Cat Stevens’s “Trouble” from Hal Ashby’s “Harold and Maude” is sad and brilliant.  I remember seeing “Harold and Maude” multiple times on cable TV during the summer of 1983 and was always struck by how effectively Cat Stevens’s songs were used in the context of the film.   While many films have since aped its use of pop music to drive the plot of a story, this was one of the first and still one of the best.