Maybe this is old news but I find Wordle to be quite addictive (specifically the “Randomize” button for a non UI-guy like me). Both the design and the animation are nice.
Wordle seems to work best on feeds. I like the ability to ignore common words but you’re limited to one language which doesn’t work too well for this blog Bistro! which doesn’t have French-only or English-feeds feeds.
Below are a few image maps from the various blogs I (co-)author (Bistro!, TheAquarium, Stories).