Oh man, where to start and stop! Ok, a few easy/obvious tracks just to warm things up a bit:
Stones: 2,000 Light Years From Home/We Love You
Beatles: Tomorrow Never Knows/Strawberry Fields Forever
Genesis: Watcher Of The Skies
Hawkwind: Warrior On The Edge Of Time/Golden Void
King Crimson: Epitaph/In The Court Of The Crimson King
Zombies: Care Of Cell 44
Pink Floyd:A Saucerful Of Secrets/ Julia Dream
Moody Blues: Legend Of A Mind
Yes: And You And I