But, what I really want to talk about is the PDF file. It has proved to be a great reference. The page numbers in the index are hyperlinked, so I usually just skip to the index and click the page number and it takes me right where I need to go.
I'd like to encourage all book authors to provide this. It's not only very convenient from a user's perspective, I think it's a good marketing tool. Some folks may not want to shell out $50 for a new book, so you offer them a PDF at half the price.