I personally use cinema 4D for rendering my 3D models. It may not be free like wings and blender and it may not me the best tool for modeling with, but it does a gorgeous job at rendering. In fact what me and my friend used to do was model in wings and then import them into cinema 4D to texture and render them. There are many type of design like animation, web design, graphic design and so on. If I talk about 3D design than its uses on interior design, furniture design, property stretcher. My favourite 3D design software are Hyper drive, LuxRender, Photo Realistic Render Man and so on.