I love working to some kind of (controlable) background noise. Something I can mostly ignore while working, but that I can focus on when loosing my train of thought. Mostly I use music but lately I have found that (some) movies helps me as well.
Why watching a movie while working can work
Ok, so first of all - I don't know. But I have some ideas.
Having a movie on one screen and work on the other is a little like having music running - except you now cover (up to) two senses. The most important part is not having a movie running that you have to look at all the time - and preferably one with a good soundtrack.
Watching a movie you have seen multiple times allows you to mostly ignore the movie, but let your subconcious follow along. This means when you are stuck working - you can look at the movie for a couple of minutes - instead of going to facebook, hackernews or reddit. Going to websites for a short procrastination usually means spending too much time there. Looking at a movie you have seen dozens of times allows you to quickly move back to working when you have cleared your head.
Why social network works for me?
First of all I have seen it many times. But for some reason seeing a movie about people writing code and getting success because of that seems motivating in and of itself to me.
I have used the soundtrack to the movie as background noise for work many times over last couple of years - so it's familiarity to my work situation keeps my brain in "work mode" instead of "binge watching old movie" mode...
What other media stimuli could be used?
Soundtracks and classical music is always a good choice for me. But so is trance music, and metal I have heard many times.
I don't know any other movies that work as good as social network... Maybe when I at some point feel like rewatching s1 of Mr Robot - that might work as well... But most movies about writing code are either documentaries or very bad movies. Neither works for me...