To setup outlook 2007 to display message item by hovering, without opening the email, follow these steps:
1. While in Outlook, Click on View, Current View, Messages with AutoPreview
2. Click on view, arrange by, Custom, Fields,
3. Choose message from available fields and add
4. Click ok, ok
Hover an email message with your message and the email will be displayed. Long emails will not be displayed in entirety
Ex-Shell 