As the weather is pants and people may be stuck in the house or at work, lets see your submisisons, I'd like to see some hidden gems.
I'll start the ball rolling with the predictable Stairway to Heaven by Led Zep. A long slow steady build-up to crescendo with a rocking tune, preceded by a great guitar solo. It also has the linkages to folklore as well just to give it the additional layer of quality.
I also quite like Echoes by Pink Floyd, simply for its incredibly drawn out nature but with a fantastic finish.