Disconnect, the team behind privacy extensions like Facebook, Twitter, and Google Disconnect, has traditionally focused on stopping sites from sending your data back to social networks and other collection entities. These sites, however, aren't the only ones getting information from your browsing, and a new Disconnect tool, "Collusion for Chrome," will chart a map of where exactly your clicks are going.

That name ought to sound familiar — it's the same as an experimental Firefox extension that Mozilla created several weeks ago. On Firefox, Collusion opens a new, almost blank tab. As you browse, the tab adds a circle for each site, then sniffs out where that data is going. Within a few clicks, you're likely to have a tangled web linked not only to Facebook and Google, but also to comment management systems, analytics tools, and everything else that keeps a site running.Sharing information isn't necessarily pernicious, but it's easy to forget how interconnected the internet actually is

The basic idea and implementation remain the same on Collusion for Chrome, and it's clearly drawing a lot from Mozilla's work. But besides opening up the extension for Chrome users, Disconnect has tweaked the code to pick up sites that may not be found by Mozilla's purely cookie-based searches. "there are many signals besides [cookies] that can identify users for tracking purposes: IP addresses, LSOs (Flash cookies), and browser fingerprinting," says Disconnect's Brian Kennish. "Collusion for Chrome catches all these cases."

To put it to the test, we ran both Collusion extensions through a similar set of well-known sites: Slate, Metafilter, PCWorld, and so forth. Some sites, like Wired, showed the same number of connections on both browsers. BoingBoing, though, had only two links on Firefox, but eleven on Chrome. Overall, Firefox's Collusion tended to pick up social networking sites and the occasional analytics or parent company. Collusion for Chrome also picked up these sites, but it gave us far more on the side of analytics and ad services. Here's what you see after visiting the same two sites with both extensions, with Chrome on the left and the original Mozilla Collusion on the right:

Collusioncomparison

As both teams of developers will admit, this doesn't mean it's time to pull the plug on your browser. The "D" icon on both maps, for example, is commenting service Disqus, which gets notified so it can give you the chance to leave a comment. Telling another site that someone's visited isn't necessarily pernicious, but it's easy to forget how interconnected the internet actually is, and these extensions help chart the links in a way that's easily understandable.

We really only have one major gripe with Collusion for Chrome: its window size. Unlike Firefox Collusion, which opens a full tab, Collusion for Chrome appears in a pop-up window above your current tab. It can certainly be neat to see the links unfold in real-time as you visit a site, but after several clicks, the window simply gets too small, and scrolling is uneven. We also can't see an option to export the graph, as you can in Firefox. Otherwise, though, it's an excellent complement to Disconnect's standard blocking tools, and its open source development leaves it ready for community improvement. You can find it now at Disconnect's Tools page.