A lot of the greats have already been mentioned, but the one that made me go "oh yeahhhh" most enthusiastically was King Crimson - In the Court of the Crimson King.
I would like to submit :
Beck's Mellow Gold - Loser, Blackhole
Neil Young's After the Gold Rush - Tell Me Why, Cripple Creek Fairy
New York Dolls - Personality Crisis, Jet Boy
Pixies' Doolittle - Debaser, Gouge Away, and on that note, Surfer Rosa - Bone Machine, Brick is Red (I really love this song, don't understand why it isn't more popular)
Ramones - Blitzkrieg Bop, Today Your Love Tomorrow the World
T-Rex's Electric Warrior - Mambo Sun, Rip Off
Some that I really like that I didn't notice mentioned.