This interactive, my first proper stab at data visualization, was built in Processing. An experiment created as part of the planning seminar for UC Berkeley's 2011 News21 project, The Ration, it ended up published on the blog Civil Eats—after which it was Tweeted widely and picked up by Grist and The Seattle Times (by which time I'd been alerted to a flaw in the USDA's dataset).
I've since learned a lot more about data visualization (namely, that differently-sized circles aren't the best way to show differences in values), but I think that this piece still works well as a way to get people engaged with the topic of obesity.