Privoxy

"Privoxy is a non-caching web proxy with advanced filtering capabilities for enhancing privacy, modifying web page data, managing HTTP cookies, controlling access, and removing ads, banners, pop-ups and other obnoxious Internet junk. Privoxy has a flexible configuration and can be customized to suit individual needs and tastes. Privoxy has application for both stand-alone systems and multi-user networks." read more...

Website: http://www.privoxy.org