Steal This Book is his book is his most famous work and is an interesting, if troubling, place to start. It is a combination of ways to get things for free if you don't want to work, minor ways to disrupt the establishment and how to make bombs and do other violent revolutionary activities. I remember reading it in high school and telling my American history teacher that Hoffman talked all about how to tear down society but not how to build it up. I recommend the book as a starting point for Hoffman because it gives an insight into the "revolutionary" thought of its time, but it is with reservation because I really don't like the parts on bombs and other violent action.