This looks interesting:
Bill gates duly trumpeted: "The WorldWide Telescope is a powerful tool for science and education that makes it possible for everyone to explore the universe. By combining terabytes of incredible imagery and data with easy-to-use software for viewing and moving through all that information, the WorldWide Telescope opens the door to new ways to see and experience the wonders of space. Our hope is that it will inspire young people to explore astronomy and science, and help researchers in their quest to better understand the universe."
It is available for Mac and PC.
Full story, links and screenshots:
MS whips lens cap off WorldWide Telescope | The Register