There are a fair few differences between the film and the book. Kubrick found the ending of the book too optimistic, and I like the fact that this route wasn't taken in the film. Plus for obvious reasons underage girls couldn't be used in the theatre scene with Billyboy and his gang, and in the record shop scene! 
I was a bit unnerved by the likes of the rape scene when I watched it first some years ago, but I've become rather desensitised and have seen worse since. *shudder* I love the bleak futuristic scenery and, of course, that score by Wendy Carlos. It's now one of my all time favourite films.
And I'll admit to throwing the odd bit of NaRABat into conversations with frienRAB when I've had a drink or two. Proper horrorshow. 
