A couple of my favorites (no EP's or live albums, just studio efforts):
Between the Buried and Me - Colors, The Great Misdirect
Blind Guardian - Somewhere Far Beyond, Imaginations From The Other Side
Iron Maiden - Piece of Mind, Powerslave
Porcupine Tree - Signify, Stupid Dream
Rush - 2112, A Farewell to Kings
Soundgarden - Badmotorfinger, Superunknown