I have been a great fan of Paul Neave's site for sometime, which is choc full of visually inspiring and quirky flash fun. Imagination is quite beautiful as is the Mandelbrot set.
Now he has added some more educational offerings like a Planetarium which is a browser-based virtual planetarium of stars and planets customizable by location (latitude and longitude) and time of day.
However the standout for me is Flash Earth which is like a Google Earth or Google Maps.
Easy to use and move around, awesome on full screen mode. This is my screen shot of Uluru... I put Yulara in the search box to find it. I went to Uluru, aka Ayres Rock, six months ago... an amazing place.
If you want see any of my images full size, just click on them, then hit the back button to return to the blog.
Advantages are the speed at which the images are rendered (super quick) and the ease of the interface. Select "Bing with labels" and you have an instant interactive atlas!