phpMyProxy is a free, light and powerful php proxy script programed by eProxies.info. This free script is released under a GNU GENERAL PUBLIC LICENSE Version 3, so you’re pretty much free to use, share, modify, redistribute, etc…
It’s features are as follows: Fast and Secure, Requires a little server resource, Encode Web Address, Supports HTTP methods: GET, POST, Supports HTTP Files Uploading, Supports HTTP Authentication, Supports HTTPS (Secure HTTP), Supports Max File Size Limit, Supports Gzip Compression to save bandwidth, Supports Multiple Languages, Supports Multiple Themes, Supports HotLink Prevention, Ability to change behavior for HotLink Prevention, Ability to prevent hotlinking automatically for non-referer visits, Ability to customize domains for HotLink Prevention, Ability to set default proxy options, Ability to freeze proxy options, Ability to block hosts
It is a comparable php version of the Perl CGIProxy script by John Marshall .
At http://www.eproxies.info/directory.php  there is a directory of free for use proxies. Like what I already mentioned for the CGIProxy script, be aware that any information you send across this connection can be monitored and logged by the script’s owner!