Have you ever been working on a very important project and needed to put off the forced restart that many system administrators have setup on their domain?
As long as you have local admin rights it is a simple process of running the following command from the command prompt.
sc stop wuauserv
Sc.exe is part of the windows resource toolkit, it is called Service Control and can be used for all sorts of service manipulation. The stop word is fairly self explanitory. The final word is simply the name of the service to be stopped, in this case the service running the windows update that controls the annoying dialog.