Windows Post-Install Wizard (WPI for short) is a hypertext application designed for giving users choice. While Windows XP offers many ways of customizing the setup process out of the box, its major drawback is the lack of being able to select which applications an end user may install. In the past, end users and administrators needed to either download the files manually, or create overly complex scripts that could only be used once. WPI allows you to create one image, which can then be custom configured, and optionally, automated, so that end users can install any applications.
http://www.wpiw.net/index.htm