Swans - The Seer
OK, might be too soon since I only listened to it twice (it's a 2-disc album that also includes 32-, 23- and 19-minute tracks - I rarely have the time/mood to dedicate myself to it) - but so far I'm pretty convinced this is one of the greatest albums ever. Well, it's Alternative/Post Punk - not for everyone. But if you like that kind of music, try it.
What's amazing, some fans consider it their best album and it was made when the band was ~30 years old.