The WorldWide Telescope (WWT) is a Web 2.0 visualization software environment that enables your computer to function as a virtual telescope—bringing together imagery from the best ground and space-based telescopes in the world for a seamless exploration of the universe.
Quoted from WorldWide Telescope
Here’s a link the TED presentation about the WWT:
http://www.ted.com/index.php/talks/view/id/224