A program to view email boxes?
Mail Viewer is a standalone, portable software program for Microsoft Windows operating systems that can display a wide variety of formats used by Microsoft in its interface. It can read and display .idx, .mbx and .dbx message databases used in Microsoft Outlook Express 4,5 and 6 as well as Windows Vista Mail and Windows Live mail message databases.
Looks like an answer to an increasing retrival problem and format hell. How to store (or backup) mail communication data in an interoperable way?
Sköne Oke 
Mbox or Maildir are good open formats.