If you haven't heard of the man, John Williams has an immense resume of film scores (mostly with Steven Spielberg and colleagues). The first 3 Harry Potter films, ET, Star Wars, Indiana Jones, Jurassic Park, you name it. While surfing YouTube, I found a 90 minute medley of some of his best works with some of the greatest timed transitions I've ever heard. If you wish to hear it for yourselves, here it is.