Ghostery is free to download, free to use, and does not contain any adware or spyware. It is available for all major browsers: Firefox, Safari, Chrome, Opera and Internet Explorer.
Disconnect and Collusion for Chrome — A robust tool that will identify and block trackers, but is only available for Chrome.
Chrome Disconnect Website
Similar to DNT+ and Ghostery, Chrome Disconnect allows you to stop third parties and search engines from tracking your web activity. Specifically, this tool focuses on allowing users to disconnect from sites such as Facebook, Digg, Google, Twitter, and Yahoo without risking the performance of the sites. The tool blocks identifiable cookies while allowing you stay logged into various sites.
Collusion for Chrome
This site allows users to then see which third parties are tracking them by graphing the spread of the data from sites to tracks, exposing them, and giving users the ability to block the trackers.
Consider adjusting browser settings to control trackers.
Before downloading yet another piece of software on your computer, consider simply adjusting the settings on your browser.
Firefox: Firefox> Tools> Options> Privacy> click the box that says, "Tell websites I do not want to be tracked." Then you should set it to "never save your history" and remove cookies frequently.
Chrome: Chrome> Preferences> Settings> Advanced Settings> Privacy> Content Settings> Click, "Block Third Party Cookies and Site Data."
Safari: Safari> Preferences> Security> Accept Cookies> select "never." You might also want to consider browsing privately so your history and passwords are not stored, and thus accessible.
Internet Explorer 10: Microsoft's latest version of Internet Explorer 10 will default to a "Do Not Track" position. The browser will send a signal to advertisers altering them that users do not want to be tracked.
Evidon — A blocking and tracking tool for web publishers.
Evidon Encompass Revenue Protection: This product is designed for website owners who want to keep the intentional tracking code on their sites from spawning additional code from third parties. It allows websites to see all trackers and how they are affecting the site's performance, while securing the site's customer data.
Evidon Encompass Privacy: This is a tool designed specifically for web publishers to help them both comply with privacy regulations, ePrivacy Directive and “AdChoices” self-regulatory programs, and protect the private information of their customers. In addition to showing all of the trackers on a site, and where they are originating from, this tool also alerts web site owners of everything that needs to be disclosed to consumers about how their information is being used.