The real Fluffy Bunny author stood up!
Florian Schepper has shared his work in my call for the original author of the Fluffy Bunny theme. I immediately got in touch with him, asking his permission to distribute it again since it virtually disappeared off the internet. And with luck I must say, the same evening I was able to wrap up a RPM and a dedicated page for it.
The theme has been tested and used with KDE 4.2 (and also should work for KDE 4.0 and KDE 4.1) and it seems to be working pretty much flawless. The RPM is built under Fedora (10), but as long as your theme files are located in /home/USER/.kde/share/apps/desktoptheme/ it should work fine. The source is released under LGLP v2.1 and can, like the theme itself, be found here at: Fluffy Bunny Plasma Theme For KDE 4.