ClearMaps: A Mapping Framework for Data Visualization. An open source library for map visualisations using ActionScript, with an Adobe AIR based encoding tool for translating data from shapefiles in to vector data suitable for use with the library.
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This is a very important library. Very nice!
Despite the seminal work shown by Stamen et al. working with Shapefiles and other geographic data formats is much too complex for the average web developer to try their hand at.
Geodata is very important, but if we can't also manipulate the cartographic information to display it, we will always be dependent on Google Maps and the likes.
I built something similar to be able to display Shapefile features in Processing (for the upcoming Dutch elections) which I'll probably release right after SxSW.