Printer friendly pages, meaning pages without the navigation or other items that are unnecessary on a printed page and would lower the usefulness of a print out of the content, are a standard feature of any site that as a client you should expect and as a developer you should expect to include.

Using the Printer Friendly Module (http://drupal.org/project/print [1]) with Drupal you edit the print template files and are able to control what shows in a printed version. The module enables you to do a lot of other interesting things, too, like have all your link URLs print out, or have alternate print logos (in case you have an animated logo or something).

This is functionality you should expect or offer out of the box, and this module should be considered one of your standard modules to use on nearly all sites.