Blender

 Blender is a free and open-source 3D computer graphics software toolset used for creating animated films, visual effects, art, 3D printed models, motion graphics, interactive 3D applications, and computer games. Blender provides a broad range of modeling, texturing, lighting, animation and video post-processing functionality in one package. It is written in C, C++, and Python programming languages, and its source code is available under the GNU General Public License. Blender has been used to create many popular animated films, including the Academy Award-winning short film "Big Buck Bunny".

blender.org - Home of the Blender project - Free and Open 3D Creation Software