2005 Global Land Survey

NASA’s Earth Observatory site has a feature article on the 2005 Global Land Survey, a collection of 9,500 Landsat images captured between 2004 and 2007:

The images are detailed enough to make out features as small as 30 meters (about one-third the length of an American football field), they have been carefully screened for clouds, and each one shows the landscape during its growing season.
Some of the images are as striking as a piece of artwork. Stitched together into a single mosaic, the collection paints the most detailed picture of Earth’s land surface a person can get for free.
Before you think about ordering it, however, consider this: to view the entire thing at full size, your computer screen would need to be as big as the Hoover Dam.

See also Universe Today.