Python, as you may or may not know, is a fully object oriented language and with the newly created ArcPy module for ESRI's ArcGIS Suite, users should start creating programs following some sort of OO design.
One design pattern to follow is the singleton pattern, which can be found here.
Once you have started diving into the world of classes, name spaces, and methods, it's time to figure out how to make methods private. It's surprisingly simple to do this. To make something private in python, just put two underscores in front of your method. That's it, now only that class can access that method.
Here is a small example: