Stumbled upon Manhattan Transformations, a mapping of “Manhattan’s skyscraper district through time”. It allows you to visually layer different kinds of geographical data, such as geological formation, districting, and so forth.

It’s a well-executed Flash piece. Some of the cool pieces are the 3D flythrough (depicted above), which I’m guessing is pre-plotted rather than computed. There’s a very nice load indicator that doesn’t use the usual “loading bar” look. Digging through the site notes, it looks like this site was created way back in 2000, and was a Macromedia Site of the Day! It still holds up in 2005. Of course, I am a sucker for wireframe graphics; sue me, I’m a child of the 80s!