Privoxy

Privoxy is a non-caching web proxy with advanced filtering capabilities for enhancing privacy, modifying web page data and HTTP headers, controlling access, and removing ads and other obnoxious Internet junk. Privoxy has a flexible configuration and can be customized to suit individual needs and tastes. It has application for both stand-alone systems and multi-user networks.
Privoxy is Free Software and licensed under the GNU GPLv2.
Privoxy is an associated project of Software in the Public Interest (SPI).
Features:

• Supports “Connection: keep-alive”. Outgoing connections can be kept alive independently from the client.

• Supports IPv6, provided the operating system does so too, and the configure script detects it.
• Supports tagging which allows to change the behaviour based on client and server headers.
• Can be run as an “intercepting” proxy, which obviates the need to configure browsers individually.
• Sophisticated actions and filters for manipulating both server and client headers.
• Can be chained with other proxies.
• Integrated browser-based configuration and control utility at http://config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule and filter effects. Remote toggling.
• Web page filtering (text replacements, removes banners based on size, invisible “web-bugs” and HTML annoyances, etc.)
• Modularized configuration that allows for standard settings and user settings to reside in separate files, so that installing updated actions files won’t overwrite individual user settings.
• Support for Perl Compatible Regular Expressions in the configuration files, and a more sophisticated and flexible configuration syntax.
• GIF de-animation.
• Bypass many click-tracking scripts (avoids script redirection).
• User-customizable HTML templates for most proxy-generated pages (e.g. “blocked” page).
• Auto-detection and re-reading of config file changes.
• Most features are controllable on a per-site or per-location basis.

• Many smaller new features added, limitations and bugs removed.

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