Synfig Studio - Just another WordPress site
Unity - The multiplatform game creation tools for everyone.
Animation Paper - Animation Paper is a software package for doing 2D animation.
Godot Engine - Feature-packed 2D and 3D open source game engine.
CrazyTalk Animator - CrazyTalk Animator, the next level of 2D animation. Create actors using any photo or illustration.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.