C++ Dependency Injection
Wallaroo is a dependency injection library for C++. With wallaroo you can easily separate the object graph from the class implementation. You can create objects and wiring them using strings, so that you can load the "object graph" from a configuration file.
C++ inline state machine library
instantFSM is a header-only C++ state machine library. Its goal is to make state machine declaration and use easy enough that it can be integrated into your projects painlessly. Have a look atp the wiki where you will find a tutorial, samples, and a cheatsheet to get accustomed with instantFSM. The only instantFSM header file is downloadable from the files section or you can check it out from the git repository.
QDwm provides classes in order to allow Qt programs to use Windows Aero advanced features as extended glass frame into client area.
Meta State Machine (msm) is a library allowing you to write high-performance expressive state machines in C++. Most UML2 features are supported.