The Mars Volta - De-Loused In The Comatorium (one of my favourite albums ever)
Sigur Ros - Takk (Agaetis Byrjun has already been mentioned, but Takk is also an amazing work of art)
Opeth - Blackwater Park (easily their best imo)
Cursive - Cursive's Domestica (probably their best, but Semantics is pretty good too)
Rammstein - Sehnsucht (mmmmmm)
Explosions In The Sky - The Earth Is Not A Cold Dead Place (Memorial is probably my favourite post-rock song ever)
Bjork - Homogenic (was never really into Bjork, listened to this album, was blown away)
Boards Of Canada - Music Has The Right To Children (amazing chilled electronic ambience)
Radiohead - Kid A (their best album
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)
Isis - Celestial (one of the greatest post-rock bands ever)
Yaphet Kotto - Syncopated Synthetic Laments For Love (simply the best hardcore album released)
Tool - Aenima (as already mentioned)
Red Sparowes - At The Soundless Dawn (just mindblowing melodic post-rock)
Miles Davis - Kind Of Blue (I've been listening to this album a lot lately, it's pretty perfect)
Mastodon - Leviathan (metal defined.)
That's all I can think of off the top of my head. I'm into post-rock quite a lot lately, thanks to Big Chris
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