I found the following interesting:
Try the free Firefox add-on GHOSTERY: https://addons.mozilla.org/en-US/firefox/addon/ghostery/
"Ghostery sees the 'invisible' web, detecting trackers, web bugs, pixels, and beacons placed on web pages by Facebook, Google Analytics, and over 400 other ad networks, behavioral data providers, web publishers - all companies interested in your activity."
- Researchers at U.C. Berkeley have discovered that some of the net's most popular sites are using a tracking service that can't be evaded , even when users block cookies, turn off storage in Flash, or use browsers' "incognito" functions.The service, called KISSmetrics,is used by sites to track the number of visitors, what the visitors do on the site, and where they come to the site from , and the company says it does a more comprehensive job than its competitors such as Google Analytics.
But the researchers say the site is using sneaky techniques to prevent users from opting out of being tracked on popular sites, including the TV streaming site Hulu.com.
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"The stuff works even if you have all cookies blocked and private-browsing mode enabled," [Berkely Researcher] Soltani said. "The code itself is pretty damning."
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[The software] makes it possible, the researchers say, for any two sites using KISSmetrics to compare their databases, and ask things like "Hey, what do you know about user 345627?" and the other site could say "his name is John Smith and his email address is this@somefakedomainname.com and he likes these kinds of things."
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The research also found that many top websites have adopted new ways to track users using HTML5 and that Google tracking cookies are present on 97 of the top sites, including government sites such as IRS.gov.
Try the free Firefox add-on GHOSTERY: https://addons.mozilla.org/en-US/firefox/addon/ghostery/
"Ghostery sees the 'invisible' web, detecting trackers, web bugs, pixels, and beacons placed on web pages by Facebook, Google Analytics, and over 400 other ad networks, behavioral data providers, web publishers - all companies interested in your activity."