NASA World Wind is an amazing piece of software available for free download:
World Wind lets you zoom from satellite altitude into any place on Earth. Leveraging Landsat satellite imagery and Shuttle Radar Topography Mission data, World Wind lets you experience Earth terrain in visually rich 3D, just as if you were really there.
Virtually visit any place in the world. Look across the Andes, into the Grand Canyon, over the Alps, or along the African Sahara.
Although the 178MB download took some time, it was worth it. I was amazed at all of the different options available, and the amount of geographic data included in the application was impressive as well. Definitely worth a look…