go-any-proxy is a server that can transparently proxy any tcp connection through an upstream proxy server. This type of setup is common in corporate environments. It is written in golang and has been load tested with 10,000 concurrent connections successfully on a Vyatta running a 64-bit kernel.
Build status can be found at http://travis-ci.org/ryanchapman/go-any-proxy
-Ryan A. Chapman Sat Jun 1 19:17:25 MDT 2013