Even if I don't spend time doing pictures (as I scan my negs) I most often pile up 5-7 rolls of film and then go into the dark to put them in tanks all at the same time, almost always listening to music for the relaxing meditational ambience it creates.

One of my favorites is Max Richter, The BLue Notebooks, very nice classical influenced ambient music.
http://pitchfork.com/reviews/albums/...lue-notebooks/