Back in my first job we had a CD drive but somehow only one music CD, so me and the other guy in that office just kept listening to that one all day.

Now despite access to all the music in the world, I still have per-project playlists. So I might listen to the same ten songs again and again for weeks on end, as starting the soundtrack quickly puts me in the mood to resume work where I last left off.

I've also adopted a mild superstition that it's bad to listen to the soundtrack for a project that failed.