Full asynchronous proxy server can support over a large number of concurrent.
HTTP proxy written in PHP based on workerman.
Web Proxy Application built on php-proxy library ready to be installed on your server
A simple HTTP proxy to work around CORS limitations
A PHP proxy script with https and post support
PHP Proxy html2canvas
PHP Transparent Proxy Script
PHP proxy and extensible web interface forwarding standard HKP requests to a local or remote SKS OpenPGP Keyserver.