Ruzzle Solver PRO is an offline solver (aka cheater) for Ruzzle puzzles. It aims to be usable, fast, and easy to extend and improve for both users and developers thanks to a sensible and modular design. It allows you to add, replace, or update the dictionaries and the score tables, thus supporting an arbitrary number of languages.
Cube Trains is a puzzle game where you build elevated railways in a city. It features 3D puzzles, unlimited undo/redo, and smart placement of pieces. The non-linear level graph means you don't have to beat a level before unlocking the next one. The game comes with a built-in level editor, so you can build and share your own corners of the city.
Octaspire Crates! is a scriptable, skinnable, extensible, and relocatable 3D action puzzle game. All the missions, game entities (or crates), game states, and configuration of the game engine are implemented as plain text Lua-scripts. So, if you know Lua, you can write new game entities, game states, missions, and levels with any text editor, without any special development tools. New skins can be created with any image editor that can save .png images, dropped into a new subdirectory under the resources/textures directory, and changed in the configuration file config.lua. Crates has also its own (simple) implementations for all the different container classes it needs (like vector, string, and so on) to keep the external dependencies fewer.
Phlipple is a unique puzzle game. The goal of every level is to reduce a 3D shape to a single square. Elimination of squares is done by flipping edges around just like in a cardboard box. It starts off relatively easy to teach the basics, and provides hours of brain tickling fun. It's a great way to train memory as well as orientation in 3D.