So around 1998 Microsoft released Windows 98 the successor to Windows 95. This release of windows was geared much more around the internet. Web enabled widgets showed up in the File Manager, in the help sub-system, in screen-savers and right on your desktop. The novelty of placing stock-tickers, weather, calculators and other do-dads was too much to resist.
What happened? In short the idea never took off. The idea of creating little 'helper' applications was novel but had little use in real world scenarios. Part of the problem was that you had to minimize your running applications in order to see the active-desktop.
Well this month Apple is introducing it's own brand of active-desktop called "Dashboard." The concept is similar. Little web-written applications run in the background. The applications are similar in nature (calculator, sticky notes, clock, stock ticker.) The one up-side is that the crapplets applets are shown above the desktop and applications rather then under it.
I personally think that this idea will have very limited success. The key problem is utility and discoverability. Novice users are unlikely to discover and use the secret F12 key needed to show and hide these applications. While advanced users will likely prefer a single window managment metaphore that allows them to arrange and manage windows as needed. The calculator is a great example. If you're writing a paper and need to make a quick calculation it's nice to bring the calculator up quickly and punch in the calculation but the way the dashboard works you can't see the background applications clearly while the calculator is open and you can't see the values in the calcuator when the application is clearly visible. It actually adds a burdon if you want to go back and forth frequently.
It'll be interesting to see if Apple's 'Dashboard' becomes popular. My guess is this feature will go the way of the active desktop.