I'd have to say Thomas Hardy's Jude the Obscure. I read it about 8 years ago and it's themes still run through my head whenever I meet people who are highly educated and still somehow not very intelligent. Which is like almost everyday.
That is a great book. Hard to pick up just one. A couple of ones that come up to mind now are Julius Evola's "Revolt against the modern world" and Ernst Junger's "Eumeswil".