The intriguingly-named Ignis Fatui screensaver displays an impressive moving system of light particles to create a drifting effect across your screen.
There are a handful of options that allow you to control how the particles circulate, the colors of them and size and speed of them on your screen. Note that you will have to have Windows XP Service Pack 2 or later installed to run Ignis Fatui plus DirectX 9.0c or OpenGL 1.1. You'll also need a 3D Graphics Card with at least 16MB available.
Ignis Fatui is a soothing screensaver for all those that like light particle effects on their screen.