Gaia - Open Source Google Earth

Gaia is "an attempt to reverse engineer Google Earth and implement its functionality in open, portable, customizable and [extensible] way".

Although the project is far from being completed, Gaia supports Keyhole authentication, 3D earth view, navigation, layers, NMEA GPS.

It will be interesting to watch this project and the added functionality. Google Earth is a proprietary application that runs on Windows, Mac and Linux, but lacks a real API. An open source alternative to Google Earth is NASA World Wind, which, ironically, is a Windows-only application.

{ Thank you, Artur Klauser. }