Provincial Lady's Daughter (R.M. Dashwood) surprised me! Quite funny in some parts.
The Picture of Dorian Gray (Oscar Wilde) I liked a lot.
The Perks of Being a Wallflower, at one point I thought it was the same navel-gazing every teen has with the exact same analysis every teen has but it got better and the twist surprised me.
The Reluctant Fundamentalist, by Mohsin Hamid, I read in two days, something a bit different!
Edit: Stephen Chbosky was author of Wallflower. Had to go and search.