This one is more of a children's novel, but I read it as a kid and it always stuck with me.
A Wrinkle in Time by Madeleine L'Engle
Much Ado About Nothing - Shakespeare
The Prince - Machiavelli
The talented Mr. Ripley -Patricia H.
Lolita – Vladimir Nabokov
It's funny that Orwell's 1984 was mentioned in the post before this. I was going to say that Orwell's <em>Animal Farm </em>is one of the best books I've ever read. It's also easier to read.
<em>Alice's Adventures in Wonderland</em> -- Lewis Carroll
<em>Nineteen Eighty-Four</em> -- George Orwell
<em>Three Men in a Boat (To Say Nothing of the Dog)</em> -- Jerome K. Jerome