I recently finished listening to an episode of Reasonably Sound podcast about the Braaam -- that very familiar sound in movies and film trailers that sounds like an orchestra of trumpets, horns, brass, and distortion that sets a certain pace for what you're seeing on screen. Reasonably Sound has dug into a bit of the history of this sound effect and dissects it for listeners.
I've seen a few videos of foley artists at work, but the Academy of Motion Picture Arts and Sciences (the people who put on the Oscars) has this much more in-depth look at foley artists doing their job. The most fascinating thing here to me is the vertical line in the AB reels they get that help the artists time up their sound effects to the clip. It's like Karaoke with no words.