If your using Vista or Outlook 2007 then the free Outlook Preview Handler in this MSDN article by Stephen Toub gives you a whole bunch of new files including PDF and ZIP support.
Free Outlook 2007 Preview Handlers (PDF, XML…
If your using Vista or Outlook 2007 then the free Outlook Preview Handler in this MSDN article by Stephen Toub gives you a whole bunch of new files including PDF and ZIP support.