The Boost project provides free peer-reviewed portable C++ source libraries.
We emphasize libraries that work well with the C++ Standard Library. Boost
libraries are intended to be widely useful, and usable across a broad spectrum
of applications. The Boost license encourages both commercial and non-commercial use
and does not require attribution for binary use.
The project website is www.boost.org, where you can obtain more information and
download the current release.