pycpp is a free C++ class library that will help you to easily write C++ code for both, embedding and extending C++ and Python. It comes along with a code generator that uses Python itself as interface language between C++ and your Python code.
Francois's Game Library is an object-oriented library for 2D games. It attempts to cover basic techniques that are essential to the game but waste a lot of time in development. You tell the game what to do rather than how to do it.
REX: Remote EXecution Distributed Computing Services for Linux and Solaris, providing C and C++ APIs, librex library and "rexd" daemon software to implement Load Balancing Process Migration : Dump + Restore, Remote File and Resource Management.