Nokia 3D World Gaze is a pretty cool app built with the premise that the Earth is a giant sphere and we are always on top of it. What follows is that far-away continents and cities are in reality somewhere below you and not linear, like we usually think of them.
So how it works is that you simply point your phone in a direction and it lets you see through the surface (and insides) of the planet all the way to the other side. You can use it to explore your immediate surroundings or fly to any part of the world. In addition to geographical features such as continents in their real physical locations, Nokia 3D World Gaze allows you to see geotagged media, day and night regions, current location of the Sun, and other content from locations around the world.
So while looking at an area of the world, you can tap the pictures button to see pictures from that region or the latest news. The N9 version even features Wikitravel searches based on city name. Have a look at the demo to see how it actually works.