This is hands down my new favorite instructional book on comics and comic book creation.
The brilliance of Lynda Barry's approach are her exercises to "dig out of you" the ideas, characters, situations, humor and insight that you're not even aware of, or don't quite know how to access.
It helps you get past the "road block" of feeling like you have to draw well to create amazing comics or communicate insight. If you're looking for a "break-through" kind of book this may very well be it!