(sorry for being a big nerd about this stuff, but it's photography, panoramics, gigapixel images and mountains!)
Yosemite Extreme Panoramic Imaging Project 2008
KRpano version of one of their gigapixel images
How it was done..
pix orb is a robotic camera mount, $11,000
and there were 70 photographers at Yosemite for the pano survey! That's alot of expensive equipment
MS Silverlight page of the map with the images, you can just keep zooming in, that's incredible resolution!