Proxomitron!

Adguard is an unique internet filter that removes ads, ad-trackers and blocks websites with viruses & malware.

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.

Ad Muncher is a powerful advert and popup blocking system for all browsers and advert-displaying programs like Pando, SopCast, ICQ, Morpheus, Kazaa, Grokster, Opera, PalTalk, iMesh, Bearshare, LimeWire, TVAnts.

A small and fast caching web proxy (a web cache, an HTTP proxy, a proxy server). Polipo can be used in place of ad-filtering, privacy-enhancing proxies such as Junkbuster, Privoxy or WWWOFFLE. As Polipo has much more refined HTTP support, it doesnt impose the speed tax usually associated with such proxies.

State-of-the-Art Ad Blocking Technology for home and business from AdFender.

Karma Blocker is a lightweight ad blocker which is directed towards the more technically advanced users and gives great flexibility to block elements with its custom rules. It uses a Karma (or score) based weighting of objects, similar to popular spam filtering solutions like SpamAssasin.

Proximodo is a loopback proxy server, seemingly a fork of proxomitron though likely abandonware. Unlike Proxomitron its developer is not existentially challenged. Additionally Proximodo can use Proxomitron filters. Unfortunately it does not support SSL connections. This could be one answer to browser fingerprinting. It is a less browser-intensive mode of adBLOCKing / adBLOCK / adBLOCKer.

Better Pop Up Blocker improves the default pop up blockers for Google Chrome and Apple Safari by blocking pop up windows opened by javascript, & other annoyances like alert, prompt, and confirm boxes. These popups often occur when you simply click on what looks like blank space or text that shouldn't do anything, let alone annoy you with a pop up window.

Tinyproxy is a light-weight HTTP/HTTPS proxy daemon for POSIX operating systems. It is free software, and supports transparent and reverse proxying.

Quero AdBlock IE XML is an InPrivate Filtering XML-based Ad Blocker for Internet Explorer 8 and Quero AdBlock IE TPL is an ad blocking Tracking Protection List (TPL) for Internet Explorer 9.Both are based on the Adblock Plus EasyList.

Safari AdBlocker is the only 64-bit ad blocker built for Mac OS X 10.5+ to integrate directly into Safari, for minimum disruption to your browsing experience.Safari AdBlocker supports the use of AdBlock Plus subscriptions (urls with the prefix "abp:") - and will be updated automatically, each week.

NoAds is an adblocking extension for the Opera web browser.

BFilter is a filtering web proxy. It was originally intended for removing banner ads only, but since then its capabilities have been greatly extended. Unlike most of the similar tools, it doesn't rely on blacklists (although it does support them). Detects ads heuristically, much like modern anti-virus software manages to detect many viruses unknown to it.

Lusca is a fork of the Squid -2 development tree. The Lusca project aims to fix the shortcomings in the Squid-2 codebase whilst maintaining the the Squid-2 functionality and stability.