How to display UI on logon screen in Windows 7

Question

I would like to display an UI that interacts with user on pre-logon screen (the screen where users usually enter their username/password)
I read that the architecture of

Answer 1

One way to get UI to show up without anybody logged in is to have a login screensaver. Your code (which could be .NET) would run after the timeout up until either you exit or somebody presses Ctrl-Alt-Del.

There are limits to what you can do as a login screensaver, but it may work for you.