I have been converting some topographic maps into 3D STL models that are ready for 3d printer. Models I've made include a 6 million:1 Texas elevation map, France (and some west European area) topographic map, China topographic map and Rocky Mountain National Park in Colorado.
Rocky Mountain National Park
They are free to download.
I found these 3d elevation maps pretty neat because I can touch and feel them and gain a much more intuitive understanding of geology.
I am making more of these 3D elevation maps of course. And feel free to leave a comment if you would like to see some other place in 3D.