IdleTimePro

Working for a long time in front of your computer can be a tedious activity, but there are various ways to customize your workspace, making it more user-friendly.
IdleTimePro is a third-party application that can help you set a user-defined web page as your screensaver. Note that, in order to run as intended, this application requires you to have an Internet connection, Internet Explorer and Java Runtime Environment on your system.

Basic screensaver utility with minimal configuration settings

Since it is portable, this application does not require you to install it on your computer, it does not modify any Windows registry entries nor does it create any additional files or folders. It comes with an unattractive user interface and a few simple functions, thus allowing you to access them without effort.
Due to its simplistic concept, it does not feature any form of help documentation, therefore, if you have no previous experience with this kind of software, your experience might be based on trial and error.

Allows you to configure the web address you want to set as a screensaver

This application allows you to replace your traditional screensaver with a web page of your choice by setting it from the Configuration menu. Specifying the desired address is the only adjustable parameter that the program allows you to modify.
Unlike a classic screensaver, it does not react to your mouse movements, but you can close it by clicking the dedicated Exit button from the top left corner of the window.

As a conclusion

To wrap it up, IdleTimePro is a lightweight application that allows you to display a web page of your choice every time your computer enters in idle mode. It comes with a plain user interface, does not provide you with standard screensaver functions and specifying the desired URL is the only parameter that you are allowed to modify.