I was just sitting here thinking about this, and while the slideshow feature in OS X has partially brought such a thing back to life, well...
There was a concept brought up WAAY back when Windows 98 was introduced, I know I'm going to get a lot of flack for even thinking about such a thing existing in OS X but there were such things as "channels" that you could subscribe to...
In some instances these channels had perks such as custom live screensavers -- it'd pop a webpage in full screen when your screensaver came up (well sorta) but it was meant to act as a live screensaver, maybe have a stock ticker and some up to date news headlines or something -- but still have the personality of a screensaver.
All the talk lately about 10.4's dashboard reminded me of the active desktop days and of course -- the channels they presented. It'd be kinda neat if say, you could have a few random live video feeds (city webcams or freeways), followed by maybe a calendar, recent events, or even stuff that you might only pop up to your computer for a second to do during the day -- like add a sticky to it or hit up calculator for a moment..
In essence I'm saying a flexible dashboard on crack, that can be used as a screensaver. The widgets, if necessary, could relocate themselves every few minutes as set in preferences so that it ACTED like a screensaver, and perhaps the background could actually be a normal slideshow screensaver.
Yeah flame on, but it'd be awesome to have stuff like this. While I'm at it, and I know it's unrelated but for those who make desktops, here's a suggestion to take advantage of the OS X rotating desktops thing: make a folder with a desktop picture that has 24 or maybe 48 variations, so that every 30 mins to an hour, your computer's desktop changed slightly to reflect what time of day it is

yet again just a geek thing.