VAPOR is the Visualization and Analysis Platform for Ocean, Atmosphere, and Solar Researchers. VAPOR provides an interactive 3D visualization environment that runs on most UNIX and Windows systems equipped with modern 3D graphics cards

World Wind is a free, open source API for a virtual globe. It provides a rich set of features for displaying and interacting with geographic data and representing a wide range of geometric objects.

Cesium is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin. It uses WebGL for hardware-accelerated graphics, and is cross-platform, cross-browser, and tuned for dynamic-data visualization.

With the OpenWebGlobe SDK you can create your own virtual globe applications running in the web browser!