Day 31 of the 40 day book challenge is 'a book that everyone else seemed to love except me'.
I can't think of one, I'm afraid, so I'm going to direct you to Scott Pack's recent post about Disappointing Classics (and the many, many comments!).
Classics-wise, I hated Middlemarch when I read it at uni, but I know lots of people adore it so I feel a bit bad. Maybe I'll try it again one day. (But probably not.)