Unity - The multiplatform game creation tools for everyone.
Mendeley - Easily organize your papers, read & annotate your PDFs, collaborate in private or open groups, and securely access your research from everywhere.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.