Aestesis'98 v1.31 - video effects based on real time sampling and analysis. Also a few other screensavers Cthugha98 - an oscilloscope on acid. For lots of computerplatforms. Can use Direct X Geiss v4.24 - swirling glowing gas screensaver. One of my favorites.
New version has more presets and maps.
Also as WinAmp plugin and DOS-version. This program is like a brain candy tripatron thing. Also Spectrum Shift Designer and Screensaver Simple Harmonic Motion - 12 Lissajous type patterns based on data files supplied. They are pretty cool and do well on video. Also a CD-player that controls the 3 screensavers.