The World Bank recently launched its Open Data Initiative which, at current, provides free and public access to over 2,000 World Bank datasets as well as the thousands of individual indicators contained in each overarching set. This data, once available only to World Bank subscribers, is drawn from both original World Bank research and self-reported statistics from the countries profiled. The data is organized by country (look here for data on the United States); topic (want to know how many internet users per 100 population worldwide?) and economic indicators (% or rural population, anyone?) There is also an extensive collection of microdata (i.e., individual household data in the developing world.)
This data should provide a boon to policy analysts and business consultants with an interest in the developing world.
Also see this Stephanie Strom piece in The New York Times on the Open Data Initiative which profiles some of the datasets and provides background on the thinking that led to the creation of the repository.