Here's one I read twenty years ago, and still remember, so it must be good. I offered it to Dave, who was looking for a book to read. Dave looked at the cover and said "You're kidding, right?" I said "No, serious. You'll like it." He said "I don't like Science Fiction." I told him he'd like this one, take it and get out of here. He took it only because it was all he was going to be offered.
Next day he said Yes, it was good, but he doesn't like short stories. I told him it wasn't short stories. He said yes it was, he'd finished the first one and was reading the second. I said no it wasn't, keep reading, you'll understand, get outa here.
Bastard never gave it back.
Book is "The Fifth Head of Cerberus" -- Gene Wolfe. A clever, intricate little book, a bit like a jigsaw puzzle. Or maybe more like a complicated piece of machinery, all its parts fitting together perfectly, and working perfectly, as perfect machinery would, were there ever any such thing as pefect machinery. Science Fiction not of the Space Adventure kind; rather an adventure in psychology, sociology and anthropology.