Graham,
If that's what you want, then you can display them two different ways:
1- Just put those docs out on a server that can be reached by URL. For example, create a menu item called "iPhone User Guide" with Type of URL. Then the URL would be: http://manuals.info.apple.com/en/iPhone_User_Guide.pdf
This option gives you easy control over opening the doc in a new window, the same window, etc.
2- Another way would be to store the Docs inside AwareIM in the SystemSettings BO. Let's say SystemSetttings.CollectionLetter would be the first one. An administrator would load the CollectionLetter document into AwareIM for all users.
Create a process called DisplayCollectionLetter that says:
DisplayDocument SystemSettings.CollectionLetter
Create a menu option with Type of "Start Process" that starts "DisplayCollectionLetter".
Tom