Reading through this thread, I knew Spawny would suggest Imperium. It is indeed awesome! 
As is Davidian on Burn My Eyes!
Also:
At the Gates - Blinded by Fear
Death - Symbolic
The Meanies - 10% Weird
Mr. Bungle - Quote Unquote
Pantera - Mouth For War
Pantera - Cowboys From Hell
SYL - the first song on City, whatever's it's called
And perhaps the best of all:
Opeth - April Ethereal
As is Davidian on Burn My Eyes! Also:
At the Gates - Blinded by Fear
Death - Symbolic
The Meanies - 10% Weird
Mr. Bungle - Quote Unquote
Pantera - Mouth For War
Pantera - Cowboys From Hell
SYL - the first song on City, whatever's it's called
And perhaps the best of all:
Opeth - April Ethereal
