#1
I recently discovered a pretty deep underground genre called Dark Ambiance.

I found out about it by listening to some old soundtracks from Silent Hill and Resident Evil and looked more into what type of music these are exactly, to which found this side project called "Lull" which was made by the ex-drummer from napalm death Mike Harris I think. There are also a few other bands that make this type of music.

Lull-
http://www.youtube.com/watch?v=-r6Jv53y1Dw

Silent Hill (white noiz)-
http://www.youtube.com/watch?v=xS6HX2m-HNY

Resident Evil (training facility)-
http://www.youtube.com/watch?v=glnFOgOb9b0

Also I don't like it "cuz it r eval lol" I actually find it pretty relaxing.
#4
Try out Procer Veneficus' album Argo Navis (2011). It's dark ambient with a space theme. The sounds are so simple, yet so potent.

Procer Veneficus - Bloodsleep
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