It's quite amazing what WWT enables you to see from your desktop. The service goes well beyond the simple browsing of images. You can choose which telescope you want to look through, including the Hubble Space Telescope, the Chandra X-Ray Observatory Centre, the Spitzer Space Telescope or others. You can view the locations of planets in the night sky - in the past, present or future and also view the universe through different wavelengths of light to reveal hidden structures in other parts of the galaxy. Take a break and take a look!
Nice 5 minute demo at http://edge.technet.com/Media/WorldWide-Telescope-video-demo-and-information/.