Galois is a computer game of the "falling blocks" type, but with unique features. Unlike most other games of that type, it is not limited to blocks made of four two-dimensional, square bricks: you can choose among several different brick shapes, blocks composed of more or fewer bricks, and even between two- and three-dimensional games.
Erebus is a 2D real-time role-playing game. Though in its early stages, it is already playable with three quests. It is a classic point-n-click style RPG, with dungeons to explore, enemies to fight, NPCs to talk to, sub-quests to complete, scenery to interact with, weapons, treasure, and other items to find.
LinRadiant is a level (map) editor for FPS games that use id Software's engines (Quake 1/2/3). It is a derivative of NetRadiant with an improved build system. It is very easy to build, even for people with little experience in software development. It has built-in support for the following games: Darkplaces, Wolfenstein:ET, Nexuiz, OpenArena, Quake, Quake 2, Quake2world, Quake III Arena, Q3MIN, Tremulous, Warsow, and Xonotic. The package contains a lot of useful documentation (mapping tutorials, technical documents, etc.) that are automatically installed and can be accessed from within the editor.
Pioneer is a space adventure game set in the Milky Way galaxy at the turn of the 31st century. The game is open-ended, and you are free to explore the millions of star systems in the game. You can land on planets, slingshot past gas giants, and burn yourself to a crisp flying between binary star systems. Pioneer has a sneaking resemblance to Frontier: Elite 2.
Digbuild is a game that provides a randomized, voxel-based world for the player to explore. In this regard, it’s very similar to Minecraft. You can create and destroy blocks, and thus you can build castles and any other structures that spring to mind. Digbuild has several improvements over Minecraft. The world has infinite height, so you can build structures as tall as you like. Different blocks emit different colors of light, and colored glass blocks filter the light that flows through them. Materials can be translucent. Textures can be bump-mapped and specular-mapped, so glass is shiny and rocks are rough.