http://www.sandboxgamemaker.com/
Platinum Arts Sandbox Free 3D Game Maker is a free open source 3D Game Maker, world creator and 3D Game Design program currently being used in many schools throughout the world that allows kids and adults to create their own video games, worlds, levels, adventures and quests, even cooperatively! The goal is to make it accessible to kids but also powerful enough for full game projects. With a simple click and roll of a mouse wheel users can modify the world however they want. In the words of a nine year old Sandbox whiz I babysit for, “Press Edit and go fulfill your dreams!”. Now features new game modes such as sidescroller, machinima, kartmode, RPG, and more!
Опенсорс, все дела. Насколько ценен не знаю - судя по описанию - что-то полезное, кому не лень - запилите новость.
