WorldWide Telescope, developed by Microsoft's research arm, knits together images from the Hubble Space Telescope, the Chandra X-Ray Observatory Center, the Sloan Digital Sky Survey, and others. Windows users (only) can browse through the galaxy on their own or take guided tours of different outer-space destinations developed by astronomers and academics. The application allows viewing from different wavelengths such as X-ray, visible light, and hydrogen-alpha radiation. Business Week has a review and some background on the project, which has been in development for years. Google Sky beat them to the punch but Business Week opines that WWT's interface is superior.