By mere chance I stumbled upon Lee Byron's beautiful visualization of last.fm listening behaviour/s (see the large panoramic graphic at the bottom of t/his page).
That would be a wonderful thing to have for one's tags, too; wouldn't it?! Imagine your tagged terms displaying the development of your focus of interest at your blog like that. :-) Clickable, of course. ;-)
Too sad that I'm not a capaple flash +/o code wrestler; otherwise I'd be on it in a snap. *sigh*
Any able fiddlers out there who feel tempted?