Book as Resume
Give a book as a resume and get hired where you want to work give you the process of writing a book to get hired into the company you seek to work for. Before working for a company you should learn what matters for them and what are the great ideas they could try to achieve their goals.
Book as expertise signal
books are always expertise signals.
Each book writer is an expert at what she or he has written.
Seth Godin is an expert at everyone is an expert and in permission marketing.