Minetest - Minetest is a near-infinite-world block sandbox game and a game engine, inspired by InfiniMiner...
The Incredible Machine - The Incredible Machine is a Physics-based Puzzle and Single-player video game Kevin Ryan and published by Dynamix.
Minecraft - A block-building game that allows you to create and explore entire worlds from scratch.
Crazy Machines Elements - Crazy Machines Elements is another installment of the multi-award-winning video game series which allows the player to create a crazy machine by combining numbers of items.
Terasology - Terasology (started under the name Blockmania) is an open source project started by Benjamin...
Rigonauts - Engient Inc.