http://bandcamp.com/files/10/13/1013636536-1.jpg

Loved it instantly.

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Trist- Hin-Fort
This was my first dive into ambient black metal. I was a little bit intimidated by this album, seeing as the first song spanned 60 minutes long. But boy, did those 60 minutes go by fast.
The song 'Hin' is one of the most complex, layered pieces of music I've ever heard. There is a constant, low frequency humming throughout the song, but melodies and little motifs are hidden underneath it. I've read that it's like "the music equivalent of staring into the void," and that is probably the best way to describe it.

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Bjork- Vespertine
Ol' Bj has released a lot of good material in my opinion, but this tops it for me. It's been described as "a winter sweater for your ears." Warm, fuzzy, and intimate, it fits the bill pretty well.
And yes, some of the lyrics can make an old lady blush.

There have been many albums that clicked with me on the first listen, but I'm gonna mention a relatively recent one. Hands down the best first listen in a while:

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Robert Wyatt - Rock Bottom

This album completely hypnotized me right away. Such an emotional, deeply layered music you don't hear everyday. It's one of the very rare albums that made me want to listen to it again right after it finished, and again...and again. And I have to thank MB and The Prog & Fusion Album Club for bringing it to my attention, because, although Robert Wyatt was on my 'to hear list', who knows when would I actually check him out. I'm still listening to this album very often, so suggestions for his other albums will be appreciated.

London Calling, definately! All of the tracks the highest quality, and fit together perfectly. Brilliant.