ATI Screensaver - ScreenSpace is a screensaver released by ATI secretly that required you knew where to find it.
It's a deep space-themed screensaver that uses many fluid flow simulation effects for things like nebulas and gaseous planets.
The screensaver should work with any DirectX9 Shader Model capable hardware, but it was designed for the Radeon X1900, so if you are running it on something less powerful, it may be rather slow. Of course, this was released in 2005 or 2006, so odds are your graphics card is capable.
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