DailyRadar uses a stream graph to display trends over the past few hours. The small applet lets the user choose between different topics ranging from Technology to Entertainement.
The size of the applet and the used color scheme diminish the usefulness but it gives a quick overview at the first glance. What I would love to see DailyRadar doing is opening up this small application and let the user customize the input. This could be an intersting method to measure, track and compare trends (in a similar way trends.google.com works)
The visualization method reminded me of the LastGraph project, which I highly recommend if you haven’t come across it yet. LastGraph uses data from last.fm and creates a stream graph visualization of the listening history.