Couple more threads with horror movie soundtracks and dark classical music:

http://www.horror.com/forum/showthread.php?t=54887

http://www.horror.com/forum/showthread.php?t=54850

Depending on your frame of mind, anything by Lustmord. Lustmord is pretty much the God of dark ambient. He is easily one of my favorite musicians ever. I never tire of listening to his music.

http://www.youtube.com/watch?v=bRVNvztrlR8
http://www.youtube.com/watch?v=OXfjQqM17NE
http://www.youtube.com/watch?v=ZD4H-E0UT0Q
http://www.youtube.com/watch?v=bpg03048Yow

Many thanks for the links to the classical and movie soundtracks threads-also for the youtube clips (I'll deffo chase up Lustmord). This discussion can include albums by artists who don't usually specialise in scary music-hence my inclusion of the Cocteau Twins debut album (their only goth album they became much lighter later on)and Alpha Centuari (I find that particular album by Tangerine Dream scary but agree not all their stuff is). I have a growing list of albums to check out. I like lying back with a full scary album. Great stuff everyone :)

that was wack. slow, quiet, boring....

Soundtrack to THE OMEN. "Ave Satani" is the scariest combination of sounds I've ever heard.

That made me think of the album "Tubular Bells" by Mike Oldfield.

You're reminded me I need to get a copy of that album.

I like Bernard Herrman's soundtracks from The Day the Earth Stood Still and Citizen Kane, and his shower scene music in Psycho. Good to listen to late at night.

I should add Lisa Gerrard's "The Mirror Pool" (1995) to this list.

And also

Cranes-Forever (1993)