Hessian Fable: "The Glass Bead Game" by Hermann Hesse

The Glass Bead Game - Hermann Hesse, Richard Winston, Clara Winston, Theodore Ziolkowski

I read this in German a long time ago (2002-06-15).

I suppose it depends on whether working through the difficulty brings you genuine insights into the human condition. I'm ashamed to say I've only read one book on this list - Ulysses - and enjoyed it. I like modernism, and Joyce's Portrait of the Artist as a Young Man is one of my favourites. Woolf is a bit daunting, but Mrs. Dalloway is superb.
If you're into stuff like this, you can read the full review.