Google May Stop Using Cookies to Track Web Users
finance.yahoo.com
finance.yahoo.com
One way I can think of would be to use ETag headers, which are intended to be used for caching but can be abused for tracking purposes[1] since by definition the browser is required to send back the server-provided ETag value.
Alternatively (or additionally), browser fingerprinting[2] seems like the perfect candidate technology to replace cookies for tracking purposes, since it can't easily be "cleared".
[1] http://en.wikipedia.org/wiki/HTTP_ETag#Tracking_using_ETags [2] https://panopticlick.eff.org
Much better than cookies, because the user can't delete anything. Plus the fingerprints would still work across browsers (I think).
This doesn't seem quite right to me. I've been using Chrome's built-in third party cookie blocking for at least a couple years now. Coming from Firefox, that was one of the biggest things I missed at first in Chrome, so it remember being relieved when it was added relatively quickly.