I haven't had much luck with recommendation systems for books, music, and movies. But the other day I happened to be looking up The Paper Chase--one of my all-time favorites--on IMDB and took a look at the "People who liked this also liked . . ." It listed 22 movies, of which I liked 13 and most of those I really liked.
I guess I'll pay more attention to IMDB's recommendations from now on.
For an interesting look at the mechanics of recommendation systems see "Deconstructing Recommender Systems: How Amazon and Netflix predict your preferences and prod you to purchase".