Negotiator is a browser extension that makes it its sole mission to increase your browsing security and privacy by allowing you to control cross-site requests and to create lists of sites and the referer that should be sent to each one.
Now, before we go even further, we should explain that an HTTP referer (not referrer, mind you) is a header field used to identify the address linked to the requested resource.
This tool comes in the form of two extensions, one for Chrome and the other for Firefox. That said, privacy-orientated Firefox users might also be familiar with two other similar extensions, namely RequestPolicy and RefControl and, it might be easy to think of Negotiator as a combination of both.
As with most Chrome extensions, Negotiator for Chrome can be effortlessly deployed on your favorite browser with a simple mouse click on the "ADD TO CHROME" button from its official page.
Click the extension's icon from the right side of the address bar, and you are met by a compact, no-frills UI. You are provided with a list tracked requests for the current website and, of course, with the possibility to quickly pass, clear or block them. Basically, you will have to manually define what you want to block.
You will also notice two more self-explanatory sections, namely Filters and Tracked, but the one that might be of more interest to you is the Options section. From here, you can set the filter synchronization to browser- or local-only, change the preset action for new filters, enable or disable aspects for filter matching, as well as customize an essential variety of default actions.
All in all, there's a good chance that a web-master, especially a privacy-orientated one, will find Negotiator for Chrome to be of great use. The tool can be neatly integrated with your browser of choice, it's quite straightforward, and it doesn't seem to be using a lot of resources to get the job done.