Sadly, many people here seem to be reviewing the "unregistered version"... and comparing this to Red Pill. Red Pill is a free saver that does what the unregistered version of MatrixGL does very well, if not better for some people... no argument there.
But the full version of MatrixGL must be seen to be believed. Honestly, I can hardly believe it is the same product... there are so many cool options in the full version that it makes my brain hurt... video, audio, picture rotation, transparent to desktop, log files as streams, options, options, options.
While the unregistered version doesn't seem to stand out very much...
The registered version is EASILY one of the best screensavers out there. In a word: Unbelievable.