I’m working on a mobile application demo that relies heavily on the Geonames service and in the process started work on an ActionScript library for accessing the web service that you can find on Github. If you aren’t familiar with Geonames it’s a fantastic project. It’s a database of placenames from all over the world (over 8 million) and each has a bunch of data (including latitude and longitude) about it. The database includes everything from physical features like mountains to schools and parks in cities. And it’s all free.
The API is really basic right now and it only implements the findNearby method but hopefully it’s a start. And I want to round it out as I start to use it for more demos. It’s a really amazing amount of data.