On days off, I make coffee before trudging to the old office. As the coffee maker gurgles away, I go over what i'd written on my previous stint at the keyboard. Once the coffee maker sighs its last, I fix myself a cup, and get to work on the next section with the fresh cup of coffee.
In most cases, I like to have background music running on iTunes, to help promote the ol' Delta wave-state. So I pick the tune on the playlist closest to the mood of the section I'm writing, and loop it.
In creative writing while I was in college, I had one piece that was written to a mix of U2 and the Cranberries. Normally, though, I can't work with English lyrics in the background, so I listen to either instrumental, trance, or foreign stuff.