GeonamesDotOrgDotNet is a library that allows users to access the GeoNames API's functions from their .NET applications. Currently, the only calls that the library supports are findNearby, findNearbyPlaceName, findNearByWeather, findNearbyWikipedia, get, hierarchy, children, gtopo30, and srtm3.
New York City is probably best known for its skyscrapers and millions of people, not the trees that line its avenues. A new iPhone app goes out on a limb to give a little credit to the oaks and maples. And it's doing it thanks to open government data.
In late March, Google announced enhancements to their mapping API that gave developers programmatic access to their popular streetview feature. Now there are some very interesting streetview mashups to check-out.