There are a number of good mapping and imagery sites on the internet. One of my favorites is Terraserver-USA, which has aerial photography of virtually the entire 48 contiguous states. Over large urban areas, the site has high-detail color imagery (good enough to see cars and in some cases the shadows of individuals on the sidewalk), and the rest of the area is covered by black and white images that still have sufficient detail to identify your house.
The old Busch Stadium, St. Louis
Gateway Arch, St. Louis
B-52s in the desert, Arizona
Other than being really cool, these types of images have numerous applications in the sciences: in geology, agriculture, forestry, biology, hydrology, and other areas.
Grace and Peace