The Open Weather Map PHP Library enables users to parse weather data and history from the Open Weather Map API. The library also tries to normalize and abstract the weather data to remove inconsistencies.
Quick, what is your House of Representatives district? Many people don't know this number, or the member who represents them. The New York Times' new Districts API makes it easy for your application to answer the question for any point within New York City, though it could serve as a template for a nationwide--or even international--service.