Yeah I agree with the Twilight one, probably with Harry Potter too, as I didn't want to appear to like it because everyone else did, and it took me years before I would even pick one up, but when my best friend was obsessed I decided to try them to see what she was on about, and really loved them, and another overly popular one would be Da Vinci Code, I was curious but tend to avoid really hyped books, but my BF's aunt insisted it was brilliant and lent it to me, and I enjoyed that too