Great article with interesting approaches. Given the volumes of data that we (should) be working with, this is a problem that I've been giving quite a bit of thought to lately. The reason I say 'should' is my bias toward data warehouse stores, given my work with Business Intelligence (or OLAP). What's even more interesting is that application of Data Mining algorithms to this data and these visualizations.
My favorite from this collection is the Shape of a Song. Below is Madonna's Like A Prayer. I'd really only thought of classical musical as having such a beautiful shape prior to this. I'd often actually tried to envision the geometry of some of my favorite classical pieces as kind of a relaxation exercise - Bach, Brahms, Rachmaninoff. This site gives a new perspective to that.