The CensusCity SDK provides data to work in projects related to population, income, and any other Census data. It has been designed with modularity in mind to interact with Census Bureau APIs, Energy Information Agency, USDA Farmer's Market directory, and Socrata. Community modules include ArcGIS and U.S. Housing and Urban Development. Get started at http://uscensusbureau.github.io/citysdk/gettingstarted.html
Have you ever wondered how much traffic Twitter handles in a given day, or what software sits behind the curtain of the popular service? A recent presentation reveals some of the answers. Twitter's incredible growth becomes obvious when you compare the recent numbers to those announced at Chirp.
Here is an interview with Karthik Ram, who has co-created the rOpenSci project, which helps make REST APIs consumable by the R language. Developers can take note of this - R is one of the widely used statistical languages in the world, and has many GUIs for making advanced data mining easily available.