I'm surprised nobody has mentioned seek and destroy, thats good fun - although It drags on a bit.

Slayer - crypts of eternity has a really nice beakdown, and 'at dawn they sleep'.

Megadeth - tornado of souls - the riffs a bit on the cheesy side but its cool.

also that riff in the breakdown of angel of death (you must know the one i mean) makes me cream my fucking pants, its incredible