If you use Apple Mail on a Mac and you have a wide screen monitor, you probably wish that you could configure mail to have a three column layout so that you can take better advantage of your screen aspect ratio. It's odd that Apple doesn't offer this layout option since it's pretty standard in most mail applications (Outlook springs to mind). If you've been wishing for this layout option, you don't have to wait for Apple to fix Mail. There is a plug-in that makes it so that Mail can support a three column layout. It's called Letterbox, it works great, and it's free. What more do you need to know?