Last September I published the following project on GitHub:
As explained in the Readme page, it is a C++11 library to encapsulate numbers in objects tagged by their unit of measurement. It uses a novel approach to such well-known problem, and it adds also support for handling 2D and 3D vector physical magnitudes.
It is still in development, but it has reached a maturity sufficient for production use.
Comments and suggestions are welcome, preferably by people who actually uses or wants to use this library.