As a self-proclaimed music-junkie I am always listen to music while writing, and in general always when I have the chance to put it on. I mostly listen to the same stuff I listen in general, but I do prefer instrumental, atmospheric, heavy, progressive, experimental, anime/game OST and retro-electronic music while writing. Won't bother listing genres since we'd be here the whole day, but anything from Aphex Twin to Lorna Shore, Carpenter Brut to John Coltrane and from Burzum to Cardcaptor Sakura OST goes. As long as it's music I like.
Here's an album and a band I've been listening a lot recently while writing: