xRez has a gigapixel image of El Capitan, Yosemite. Although I am not quite convinced that the image has that many pixels, you can zoom in quite a bit and see some really cool details. John Nack on Adobe comments that the picture has 3.8 gigapixels! After going to the main site and looking at other “Extreme Resolution” pictures on xRez, I do believe their claim of gigapixel-level pictures to be quite convincing. Have a look: xRez.