Outlook 2003 and up offer an option to make New Groups (in the Navigation Pane) and quite a few users aren't quite sure what they should do with them.
I use groups hold calendars I don't want to see in the Navigation pane and to keep certain colleagues calendar's together. If I need to see the calendars, its one click on the down chevrons to show the folders and one click on the up chevrons to hide then again.
- Click Add New Group and type a name in the field.
- Drag folders from other groups to this group.
With Outlook 2007 or 2010, you won't be able to delete folders from the Navigation pane - deleting from the navigation pane deletes the folder from your mailbox or PST. Instead, you'll need to move folders to a new group then collapse it.