
You can view the messages in your Inbox (or any subfolder) by size:
1. In Entourage, select View, then Arrange By...Select Size, and if need be, also select Show in Groups from the same menu.
2. Your Inbox will now be grouped by message size: "Tiny," "Small", Medium," "Large," "Huge," and "Enormous". (If need be, click on the arrow to expand a section.)

3. To change your mailbox view back, go to View, then Arrange By... and select the desired column (i.e. Date).