http://ngm.nationalgeographic.com/wallpaper/download
I think these would be good for making presentations, EK cards, etc. They are stunning, high res pictures.
Look at this http://ngm.nationalgeographic.com/wallpaper/img/2010/02/feb10wallpaper-7_1600.jpg It doesn’t even look real.
There’s also a really cool puzzle feature that you can play with their pictures or your own. This would be good for an older child.