Book pages have a very neat feature: Printer-friendly versions (link at the bottom of the page).

 

Click this link to generate a single HTML page with the current page and all sub-pages (pages in sub-sections).

So this makes printing books and book sections a breeze, even when the content is divided into many separate pages!

 

On a side note, InfoQube has a similar feature. Select many items and the HTML export will generate a combined page of all item's HTML. 

Drupal and IQ really have many things in common... More on this here: Similarities between this Web site and InfoQube...