http://psd.tutsplus.com/tutorials/3d/3d-mini-planet/

When most people think about Photoshop, they probably don’t think about 3D. What most people don’t realize, however, is that Photoshop CS5 Extended includes some powerful tools to help you render your artwork in 3D. In this tutorial we will demonstrate how to create a mini planet using Photoshop’s 3D capabilities. Let’s get started!