Do any of you use ambient music or sound effects in your Dark Heresy campaigns? If so, what do you use?
I've been listening to a few non-DH RPG podcasts lately that do this and I'd like to try it sometime with my group. The closest thing I've found to appropriate background music is through listening to some Dark Ambient Internet radio stations, but I don't know of any CDs that would fit this bill.
Anyway, just curious if any of you do this.
Realistically, I would recommend either simply playing that internet radio station if you can do that without audio advertisements. You could additionally simply pick some song names you found particularly thematic and search for CDs that contain that song, be they artist releases or compilations.
I do use ambient music on ocasion, but always fantasy. I imagine that dnb could be good for sci-fi and dark mood of wh40k. For example, try this:
What do you think about something like the "Desolate City" track on this page? Unfortunately this is a rather expensive 3-minute track due to the licensing, but I'm just using it as an example.
http://www.mediamusicnow.co.uk/music/ambient_royalty_free_music/dark_atmospheric/
Try the bands Red Sparrowes, Isis, Russian Circles, Explosions in the Sky, Mogwai, Grails, Pelican, and Tribes of Neurot.
I've got a similar station on pandora that you can find here:www.pandora.com/
Lustmord with their classic Heresy.
Seems appropriate, somehow 
Try Last.fm- if you play their dark ambient tag you'll have streaming stuff without the annoying adverts.
Aside from that- Nox Arcana and Midnight Syndicate do some good BGM albums