If you want to create branching stories quickly and easily, this free graphical tool might just be for you. It's not likely to be useful for me without access to its source code, but non-programmers should have some fun with it.
This is how Ren'Py describes itself:
Ren'Py is a visual novel engine that helps you use words, images, and sounds to tell stories with the computer. These can be both visual novels and life simulation games. The easy to learn script language allows you to efficiently write large visual novels, while its Python scripting is enough for complex simulation games.I like that beginners can use its simple scripting language to create interesting stories, and that I will be able to use Python to make more sophisticated games. This is probably the first tool I'm going to download and try since it should be really fast to get going on the simplest of ideas.
As per the Fabula website:
Fabula is an Open Source Python Game Engine suitable for adventure, role-playing and strategy games and digital interactive storytelling. Fabula can be used as a library to develop your own games. As an alternative, you can use the Pygame-based graphical editor and the default game engine that come with fabula.With this tool, you get into programmer's territory, but still get a lot for free. I like that the engine was designed with storytelling in mind, and that like Ren'Py it uses Python, which should make it fairly easy to work with. I will likely give this one a try early on as well.
According to the Orx project site:
Orx is an open source, portable, lightweight, plugin-based, data-driven and extremely easy to use 2D-oriented game engine. It has been created to allow fast creation of games and prototypes.The reason I include this project is because I think 2D is the way to go to test story ideas, and such an engine would make creating a 2D game much easier. If the other tools aren't flexible enough to customize things as much as desired, then this might be the way to go (assuming you understand C/C++ programming). I probably won't use this one right away since I don't need the power, but I have a feeling it could come in handy later on.