A collaboration between myself and @nolski, RHoK The Hood came out of the Random Hacks of Kindness (Rochester, NY) event held in 2013 as a way to allow residents of Rochester, NY to view census data overlayed on a map of the city.
A city official at the event had presented on open data and had demoed a similar application which was, at the time, available to residents of Rochester (and required Silverlight!).
Attendees were told that the application was being taken offline in February 2014, but that a replacement wouldn't be available for some time after that.
Since the census data is all public, we decided to build our own, open source alternative. Six hours later we had a demo up and running and we took first place.
Future plans include, given the time, extending this to other cities and providing easy tooling to import data sets for visualizing.