I would love to know what others enjoy listening to while playing this game.
I've got four go to's, Fenriz' project Neptune Towers, Tangerine Dream, Nemesis, and Biosphere. Here are a couple helpful links.
First up is the "darkest" of them, of Black Metal fame Fenriz.
Caravans to Empire Algol and Transmissions from Empire Algol
Tangerine Dream are huge pioneers in electronic music, and I have to mention Kraftwerk in that regard as well. Seek out Atem, Zeit, and Alpha Centauri.
Nemesis from Finland have great works out there although some are difficult to find for whatever reasons. Their bandcamp page doesn't list all of their discography.
http://www.nemesisem.net/sky-archeology/ Live playing of the opening track to Sky ArcheologyBiosphere of Norway is great. Dropsonde, Patashnik, Substrata, and Microgravity, I can recommend.