Machinarium - Machinarium is independent puzzle / adventure game by Amanita Design
Unity - The multiplatform game creation tools for everyone.
Unmechanical - Fun and atmospheric side-scrolling puzzle adventure.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Limbo - “Dark, disturbing, yet eerily beautiful, Limbo is a world that deserves to be explored.” Joystiq. “Limbo is as close to perfect at what it does as a game can get.” Destructoid. Buy LIMBO: Special Edition.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.