1) Carlos Castaneda's first three "Don Juan" books: read them while I was in med school in the early 1970s and they ALMOST made me drop out, they were so powerful (then). I looked at one recently and thought "meh." People change.
"The Power of Positive Thinking" — I read this when I was in junior high and a real jerk. It instantly ended my jerkitude and put me on a much better path.
