I find the process of screenwriting fascinating. It's highly restrictive, forcing a writer to convey plot, characters, subtext and meaning in only audiovisual terms. Screenwriters must also use time as it's own language by constantly slowing it down and speeding it up.
In this video, John August, the internet's favorite screenwriter show us how to re-tool a scene and it's dialogue for maximum effect - and gets rid of some cruft in the process.
If you're fascinated by the creative process as much as I am, it's worth the time to watch.