Which Book Do You Prefer was created by Aris Catsambas basically and asks visitors to pick their favorite from a pairing of novels – it requests only that you vote if you’ve read both of the books in question, but otherwise you just pick your preference from the pairing and move onto the next set. At any point you can see the cumulative global ranking of THE BEST BOOKS EVER – at the moment The Haunting of Hill House , followed by The Hitchhiker’s Guide to the Galaxy.
Apparently the website was created by AI. It’s worth a few minutes anyway.
Travel Between The Pages 
They are very odd pairings, and I haven’t cast a single vote, as I haven’t read both of the pair. Given up now.
I had better luck, but found some of the pairings to be simply bizarre.