I found about this really cool mind map from Blog IDEE. Built on Mindmeister and entitled “Open Source Overview” it is a very detailed diagram depicting the open source world. The main building blocks are “Open Data” , “OGC standards” and “OSS GIS Stack”. Really, really interesting and definitely worth’s a look!
Now there is a single access point for them. DataCatalogs.org which:
…aims to be the most comprehensive list of open data catalogs in the world. It is curated by a group of leading open data experts from around the world – including representatives from local, regional and national governments, international organisations such as the World Bank, and numerous NGOs.