S5 Reloaded by Christian Effenberger http://www.netzgesta.de/S5/references.php which adds auto-scaling of images, fading, sound, chart support, extended control panel and more.
S9 http://slideshow-s9.rubyforgegithub.orgio/ Slide Show (S9) - A Free Web Alternative to PowerPoint and KeyNote '''in Ruby''' by Gerald Bauer who also rewrote the javascript part using jQuery and calls that S6 it "Easier to Understand and Extend S5 Rewrite using jQuery"
Another S6 (this one an acronym for [http://tzi.org:2000/s6.html Synchronized S5]) by Carsten Bormann which may not be found anymore provides "remote control" through Prototype http://64.233.169.132/search?q=cache:fvNekyOv2UgJ:tzi.org:2000/s6.html+s6+slideshow&hl=en&ct=clnk&cd=7&gl=us&client=firefox-a
==== S5 with MediaWiki====