Don't judge a book by its cover! Except, we all totally do, let's be honest. These are some of my favourite cover designs for mixed author collections, where a set of books by different authors are given matching or coordinated covers. I have left off very large sets like SF Masterworks or Penguin Classics, but included smaller ones - including the Penguin Leatherbound Classics, which don't look nearly as good on screen as they do in real life, more's the pity.
Some of these sets are beautiful, some gracefully simple, and some unexceptional alone but make a lovely set in combination. How many have you read?