I’ve previously mentioned that GIFs are underutilized in data visualization. Jorge Camoes put together a nice progression of Walmart stores opening in the United States from 1962 to 2007. Simple and effective. He also provides some other ways of viewing the same data, but I find the GIF is really underutilized.

The upside of GIF—especially opposed to Flash—is accessibility. The rise of iDevices means Flash excludes you from a large audience. Even Javascript is prone to run slowly on an Android or iOS device. Although it lacks interactivity, it’s a fine way to add an additional time dimension without excluding an audience.