I had a friend who toyed with the idea of writing a dissertation showing that Freud's tripartite division (id/ego/superego) resulted from his use of cocaine. You know, a couple of sniffs, and the goddamned superego just shuts up....
On the other hand, my shrink told me that some people have nice, friendly superegos. I found it hard to believe. In any case, Freud's superego seems to have been one of the more normal/mean/nasty ones.
Joanna