The EFF has a new research tool and would like your help testing it and building a sample database.  It’s called Panopticlick and it examines your browser configuration, especially installed plugins.  Your browser’s configuration is then compared to its sample database and it rates your “uniqueness”.  Since your browser configuration is available to every web server you contact, it can act as a sort of fingerprint.  The more unique the configuration, the more readily you could be tracked as you surf around the intertubes.

Firefox is my main browser and apparently I stick out pretty well, thanks to my plugins.  For example, I was a beta-tester for Quake Live and that definitely helps boost my uniqueness.  Here are the results:

Your browser fingerprint appears to be unique among the 134,447 tested so far.

I also use Opera and Explorer, but generally only to test web development in different environments.  I expected Opera to be fairly generic, but it was also unique.  This was unexpected, because I haven’t really customized it at all.  Upon closer inspection I realized that it also has the Quake Live add-ons, which it must have picked up from Firefox during installation.  The results:

Your browser fingerprint appears to be unique among the 134,632 tested so far.

And finally, Explorer, which ought to be as stock as they come.

Your browser fingerprint appears to be unique among the 136,319 tested so far.

Huh.  Explorer ought to look just like many, many others and yet it’s unique.  No plugins were evaluated, but the browser was extremely balky at loading the site and running the test, generating different errors and warnings each time.  I’ll have to look into why this is.

Oh, well.  At least the EFF now has a little more sample data to work with.  For more details on how browser uniqueness enables tracking online click here (math nerdiness ahead, but there’s a helpful glossary).