Popular proxy software

* The Squid cache is a popular HTTP proxy server in the UNIX/Linux world.*
* The HTTP-Tunnel is the most popular SOCKS and HTTP proxy server and Client for Windows.*[citation needed]
* The Apache HTTP Server can be configured to act as a proxy server.
* Blue Coat's (formerly Cacheflow's) purpose-built SGOS proxies 15 protocols including HTTPS/SSL, has an extensive policy engine and runs on a range of appliances from branch-office to enterprise.
* WinGate is a multi-protocol proxy server and NAT solution that can be used to redirect any kind of traffic on a Microsoft Windows host. It also provides firewall, VPN and mail server functionality. Its WWW proxy supports integrated windows authentication, intercepting proxy, and multi-host reverse-proxying.
* Privoxy is a free, open source web proxy with privacy features
* Microsoft Internet Security and Acceleration Server is a product that runs on Windows 2000/2003 servers and combines the functions of both a proxy server and a firewall.
* JAP - A local proxy, web anonymizer software connecting to proxy server chains of different organisations
* Tor - A proxy-based anonymizing Internet communication system.
* Proxomitron - User-configurable web proxy used to re-write web pages on the fly. Most noted for blocking ads, but has many other useful features.
* PHProxy is a Web HTTP proxy programmed in PHP to bypass firewalls and other proxy restrictions through a Web interface very similar to the popular CGIProxy.
* SJSWebProxy (SunMicrosystems) is a proxy server for HTTP and HTTPS (CONNECT) requests. It can also serve as a gateway for Ftp and Gopher traffic. It is also free for download.
* Nginx Web and Reverse proxy server, that can act as POP3 proxy server.
* SSH Secure Shell can be configured to proxify a connection, by setting up a SOCKS proxy on the client, and tunneling the traffic through the SSH connection.
* CCProxy An all in one easy proxy server for windows, graphical interface and easy to configure. Demo version supports 3 users at a time.
* NetShade An anonymous proxy server management program and subscription-based proxy service for MacOS X.
* FreeProxy Freely available proxy server for Windows. HTTP, HTTPS, FTP, SOCKS, POP, SMTP, credential authentication using basic, digest and NTLM, ban lists, cache, Web server, extensive logging.
* 3proxy Free open source proxy server for Windows, Linux, Unix, Mac OS X. HTTP, HTTPS, FTP, SOCKS, POP3, general UDP and TCP, bandwidth control, traffic limitation and accounting.
* Middle-man is also a freely available proxy server for Unix/Linux, has a web based interface, and supports HTTP/FTP proxying.
* PingFu is a proxy client for Windows for users to bypass proxy / firewall restrictions or use applications and games that are proxy unaware through Proxy Servers.
* Barracuda HTTPS tunnel and proxy client/server. Easier than VPN.
* Rhinosoft AllegroSurf is a content filtering proxy server that also provides Internet Sharing, Content Filtering, and Network Resource Management. AllegroSurf supports Windows authentication, can be configured as a whitelist if required, and can automatically block ads, popups, and other unwanted content. A 30-day trial is available. It also can be configured to function as a site-to-site SSL VPN.
* CGIProxy is the original CGI-based anti-censorship proxy script, and is still actively developed over a decade later. Notably, CGIProxy supports JavaScript through it, including most "AJAX" sites. It is highly configurable, and freely distributable for non-commercial use.