Blender is a free and open source 3D animation suite. It supports rigging, animation, simulation, rendering, compositing and motion tracking, even video editing and game creation.
YouTube Videos: https://www.youtube.com/user/solidworks
Sketchup: a free 3D drawing tool for educational use.http://www.sketchup.com/buy/education-licenses?gclid=CLDzwLmr7MMCFYVAaQodzgIASg
Arduino is an open-source electronics platform based on easy-to-use hardware and software. It's intended for anyone making interactive projects. http://arduino.cc/
