Cat's Cradle is a very challenging book, not in terms of the language, but in terms of the numerous important topics and ways of thinking the book confronts in often very subtle ways. 
 One of the things I liked about this book was that it changed my view that the advancement of science is a 'good' thing. I now realize that yes science advancing is indeed a good thing, but that truly depends of whether or not people like Mr. Felix Hoenikker get hold of dangerous substances such as Ice-9. 
 I would recommend this book to every not-extremely-religious person who has a curiousity about the purpose of the human species.