C++ networking library; aims to become part of boost; built on top of Boost asio; has HTTP client and server; and general message template.
Cpp-netlib (http://cpp-netlib.org/) is a networking library.
It calls itself "a collection of Open-Source libraries for high level network programming"; its abstraction level is at the bottom of the OSI application layer. The library provides a general message template, http request and response messages built using the general message template, and HTTP client and (in proces) server code.
Cpp-netlib aims to become part of Boost. It relies havily on meta programming (i.e. templates). Cpp-netlib is built in top of Boost::ASIO (the asynchronous I/O library within Boost).