Candlemass: A Sorcerer's Pledge
Candlemass: Well of Souls
Heathen: Hypnotized
Fates Warning: Guardian
Blind Guardian: Majesty
Blind Guardian: Journey Through the Dark
Black Sabbath: Heaven and Hell
Black Sabbath: Sign of the Southern Cross
Sepultura: Beneath the Remains
Death: Symbolic
Deadly Blessing: Deliver us From Evil
Deadly Blessing: Silent Madness
Queensryche: Queen of the Reich
Queensryche: Roads to Madness
Crimson Glory: Red Sharks
Coroner: Nosferatu
Flotsam and Jetsam: Doomsday for the Deceiver
Iced Earth: A Question of Heaven
etc.
...and when I first heard it a few years back, Anthrax: Armed and Dangerous, just because I had written the song off as a cheesy ballad for such a long time. I decided to give it another try, and about two minutes in... BAM! The transition to ballad to all-out power/speed/whatever metal song made me nearly fall out of my chair. (I was relatively new to metal at the time, ha ha.
)