Banned books

What do you think of challenging books? I don't really believe in censorship, but one of my classes this semester is focusing on this topic. We all had to find and read a book that was on the banned book list. I chose one of my favorites, The Giver by Lois Lowry. This book is about a little boy named Jonas who lives in what the author describes as a utopian society. However, as always, things are not always as they seem. I don't want to give the story away so I won't tell anymore in hopes that you will check it out.
I was surprised by some of the books on the list that my classmates chose to read. One was The Face on the Milk Carton. Who hasn't seen this Lifetime movie? Why in the world would someone want to remove this seemingly harmless book from a library? I have no idea...but those in the class who have blogged about it (www.bannedandchallengedbooksspring2009.blogspot.com) say it is b/c the girl questions authority. Come on!! Who wouldn't want to know that they have been kidnapped?
Anyway, I'd love to hear about books that you have read that you think should be banned (dirty word), or that you've heard others complain about. OR just a book that you thought was great!