Contributed By: Cliff Hobbs [MVP SMS]
To configure Outlook to have a newsgroup look and feel do the following:

1. Create a subfolder for the mail list messages.
    
2. Setup an Inbox rule to move all the messages received from the relevant newsgroup to the folder you've just created.
    
3. Select the subfolder that will contain the newsgroup messages.
    
4. Right click on the 'Subject' column header and select 'Group by This Field'.
    
5. Drag the 'Received' column header to the 'Group By Box'.

This will group your messages by subject first and then by received date. This setting works on a folder by folder basis so you can set different groupings for different folders.