The Bible, really. I'm an English major and I say it is the best book I've ever read in my entire life.
However, outside of the Bible I'm reading "The Cost of Discipleship" by Dietrich Bonhoeffer, which I'm really enjoying. I loved all of The Lord of the Rings trilogy, and I read some of Unfinished Tales, but The Silmarillion was like a text book o_X;; I couldn't push through it. C.S. Lewis' non fiction is amazing, but I'm not a huge fan of his fiction. The Lion, the Witch, and the Wardrobe wasn't too great. It was a good story but I felt like the writing was generally pretty poor. But when I read The Magician's Nephew I was really impressed with how his writing had grown since writing that first one, it was leagues better. Also Till We Have Faces, also by Lewis was great, although not a Narnian story.
But I've stopped reading a lot of fiction and have gotten into theology a good deal more, I guess it just suits me better. I enjoy non-fiction a ton more than fiction these days, which seems to be the opposite of everyone else. I just tend to like books that have a real impact on my life practically instead of books that are fun.
Some of the books on here I enjoyed to a point. I loved the idea behind 1984, but a good chunk of the middle of the book was all sex. Not a fun read. I felt like it was just a waste of paper and ink. The rest of it was great. The Stranger was just an acid trip, I think it's all hype. *shrug*