This is absolutely awe-inspiring, from photographer David Bergman.
Covering Obama's inauguration, he made a 1.4 Gigapixel composite image of the scene. Here, he describes how he did it.
The image itself is here. Follow the link and you'll see for yourself how you can zoom and pan the image to get the most remarkable fine detail.
One more word: WOW!!!
(Tip of the wig to Tim Ireland for the link)