A guy named gary has produced a widget which demonstrates in „real time“ the explosion of the social web. As you can see below, the rate of new content and interaction on the various social sites and applications is enormous! He writes about it:
I quickly built and coded the app based on data culled from a range of social media sources & sites at the end of Sept 2009.
On his site you can see more about his data sources, and you can also grab the source code for the widget.