KODE is a physics library written in C++11. It follows the Open Dynamics Engine (ODE) design, while offering far more conveniences for C++ programmers, at a competitive performance.
SimpleSignal++ is a C++11 library that implements simple signal dispatching using directly features from C++11.
Ogry is a 2D rendering engine, loosely based on Ogre. It features a scene graph with useful 2D primitives, and multiple rendering back-ends: from OpenGL (for interactive high-performance rendering) to Cairo (to export vector or pixel-based formats such as PDF or PNG).