NModule is an extensible plug-in framework for the .NET framework. It is an abstraction layer on top of the reflection API. It uses roles (defined by the application) to determine how to use a module.
Hotaru is an XNA-based Game Engine that is intended to be used for 2D Action RPGs. Game Developers can use Tonbo (a Visual Studio Plug-in) to create and distribute games that run on Hotaru.