Blender 3D is a very cool open source 3D modeling, rendering and animation program. The application is designed very well. You can use it for commercial 3D modeling. You can easily create games with Blender. Blender has an inbuilt game engine which allows games to be directly created from it. The software can also be used for interior designing of buildings and houses. The Toon shader in Blender allows 3D renderings to look more like 2D illustrations. Industrial designers can also use this application to conceptualize their ideas. Blender can be used for many other application developments and 3D authoring also.