If you haven't guessed it already, I'm a huge National Geographic fan. I've already discussed how you can download the free National Geographic POD that will update your background with a new National Geographic image each day. Well National Geographic has just added more stunning high resolution photography wallpapers to their collection. From adventure and exploration to science and space wallpapers, you can check them all out here. Just click on the one you like, select wallpaper, choose the most appropriate size for your desktop screen, add it as your background and voilà—your desktop will instantly look fabulous!