Forget cookies, even the ultrasneaky, Flash-based "super cookies." A new type of tracking may identify you far more accurately than any cookie, and you may never know it was there.

The method pulls together innocuous data about your browser, such as plug-ins, system fonts, and your operating system. Alone, they don't identify you. Together, they're a digital fingerprint.

It's like describing a person. Just saying "brown hair" won't identify anyone. But add in "5 feet, 10 inches tall," "chipped right front tooth," "size 12 shoes," and so on, and soon you have enough information to pull someone out of a crowd, even without their name, Social Security number, or any other of the usual identifiers.

Test your browser for unique identifiers without the risk: The Electronic Frontier Foundation, a privacy advocacy group, has set up an interesting online experiment at Panopticlick.eff.org. Panopticlick gathers little de­­tails about your browser and computer, mostly using Javascript. In my case, the information it gathered about my browser was enough to uniquely identify my surfing software out of more than 650,000 visitors.

More than a rumour

Peter Eckersley, a staff technologist with the EFF, says he and his colleagues decided to create the site when he heard rumours about this kind of tracking. He wanted to see how accurate it might be.

Well, it's pretty accurate. And as it turns out, its use is more than a rumour.

Browser fingerprinting was developed for banks to employ to prevent fraud. But now one company, Scout Analytics, offers it as a service to websites, and it collects not just browser data but also data about how you type, things like your typing speed and typing patterns.