David Allen's seminal work on personal productivity, Getting Things Done, stresses frequently emptying all of your capture devices to maintain a stress-free environment by promoting a manageable amount of input.
One recurring problem that Allen (and others) identify is the poor practise of using your in-box for storing information as though it were a to-do list. This is an inefficient practise I am very guilty of.
Though I make a concerted effort to transfer things from my in-box to one of the other mechanisms I have in place to act on an item; I needed some help.

Using Mailbadger I created a series of custom badges to represent, in numerical order:
- New, unread messages in my in-box
- Mail from my thesis supervisor in my in-box (read or unread)
- New, unread messages from my sweetheart in my in-box
- Total mail messages in my in-boxes (personal and institutional)
The last one, highlighted in the above image, is the important one for getting your in-box count to zero. The colour scheme doesn't draw too much attention to it, but it's a constant reminder that there are still entries to clean up in my in-box.
A simple tool to help solve a seemingly simple problem. The key is in remembering that "dealing with" mail doesn't end with marking it as read.
†I have a custom Think Different stamp icon of Pablo Picasso to replace the standard Mail.app icon.
