While working on knowledge management and semantic web technologies, I came across the Simile project at MIT a few years back. I even had a demo of the Exhibit widget fetching then displaying data from our semantic web application framework back in 2006 at the Web2 track of Solutions Linux in Paris.
Now that we are using these widgets when implementing web apps for clients, I was happy to see that the projects got a life of their own outside of MIT and became full-fledged free-software projects hosted on Google Code. See Simile-Widgets for more details and expect us to provide a debian package soon unless someone does it first.
Speaking of Debian, here is a nice demo a the Timeline widget presenting the Debian history.