This is a cool little registry hack. Simply add the registry setting noted at the bottom and the next time you minimize Outlook it will be stored nicely in your system tray next to your clock. Now you can leave Outlook open all day rather than wasting room in your task bar.
The easiest way to do this is to copy and paste the below line into a .txt file and then rename it to outlookfix.reg. Now double-click the reg file. Enjoy!
This registry key will only work with Outlook 2003, notice 11.0 as the version.