Bands with a great sense of atmosphere

Graveland - Necromanteion (demo)
Napalm Death - Few of their songs from their albums(i.e. "Contemptuous" or "Our Pain is their Power")
Programmed Cell Death - Submission (link)

Programmed Cell Death are a rather lesser known industrial/ambient group. They're not metal but they are quite distinct.
 
NDE (no one has heard of them, there were on a terrorzer fearcandy copilation) Are the most terrifying ambient bm out there. I voided my bowels and gouged out my ears. I also think mars volta get some atmo going.
 
They are only listed as NDE they are a crazy duo, german philosphy, and BM may be a misnomer. They aren't really music. They don't use things like, guitars or drums.
 
Briefly skimmed through the thread and didn't see them mentioned; Daylight Dies.