Armadillo is a C++ linear algebra library (matrix maths) aiming towards a good balance between speed and ease of use. The API is deliberately similar to Matlab's. Integer, floating point, and complex numbers are supported, as well as a subset of trigonometric and statistics functions. Various matrix decompositions are provided through optional integration with LAPACK and ATLAS numerics libraries. A delayed evaluation approach, based on template meta-programming, is used (during compile time) to combine several operations into one and reduce or eliminate the need for temporaries.
Google C++ Mocking Framework (or Google Mock for short) is a library for writing and using C++ mock classes. It was inspired by jMock, EasyMock, and Hamcrest, and designed with C++'s specifics in mind. It lets you create mock classes trivially using simple macros, supports a rich set of matchers and actions, handles unordered, partially ordered, or completely ordered expectations, and is extensible by users.
CloudVPN is a secure decentralized mesh networking tool. It allows applications to use it as a mesh transport layer for packet routing, easily creating mesh ethernet VPN, secured audio/video broadcasting or communication channels, etc. It can create secured networks with special or weird topologies, so it's very easy to create connection schemes with clustered/decentralized servers, topologies with better throughput, ring-like topologies for failover, long-line for passing through many routes, or tree topology for optimizing inter-server bandwidth needs.