In the Free Software world, Marble is the name of “a small interactive globe and geographical atlas” for all platforms (including mobile ones) where the Qt libraries can run. At first sight, Marble may seem one of those pretty, but all-in-all unnecessary software applications we all meet from time to time: why Marble when we already have Google Maps and Google Earth? As it turns out, you may have a lot of reasons to use Marble, once you know it better.
Marco Fioretti goes on to talk about its open-ness, its speed and the abilty to add datasets to it (including one's own voice for naviation). I can't say I've heard of it or used it, but he suggests its a great fit for education.
University of Camrbidge (UK) has switched to OpenStreetMap for its basemap for the online campus map. Note how it's fully atributed the map wiht a link to the new license. The map has its own APIs and uses open source code for serach and styling.
Someone on Twitter asked about WorldWind the other day. It might have been @cageyjames. I saw two projects that use it just yesterday:
1) It's part of Snowflake Software's new free ATM Viewer for AIXM data.
2) It's part of "a web-based planning, prediction and training tool, which can be used to support decisions in long-term urban planning. This was developed by the SUDPLAN ('Sustainable urban development planner for climate change adaptation') project, which has received more than EUR 2.5 million under the 'ICT for environmental services and climate change adaptation' Theme of the EU's Seventh Framework Programme (FP7)."