It's the Complete Knife Throwing Guide by Gil Hibben! In it, you'll learn exciting things like how to throw knives from a distance, choosing the right knife to throw and how to build knife-throwing targets! (No word on if the guide covers throwing knives at human targets without killing or maiming them.)
So order your Complete Knife Throwing Guide today and get started on your new, exciting talent! With skills like these, you'll be the life of any party! And chicks will really dig it too - just ask this guy.