I read in someone's LJ recently that the person wasn't certain where new members were coming from for this site.
Since the same person has a website that has three cookies, not one, like this site, why not use a referrer cookie if referrer site not known from log? Looks like one of them on that site is of that sort (best guess).
(Only cookie used here iis an "identifier" like other site has, although having that one may prevent attachment of others on return visit.)
Saw a site the other day with a bunch of cookies for sale for assorted platforms and languages. Lots of sites sell them for $5.00 to $15.00. Probably can obtain opensource for -0-. Yer gettin pretty fancy with this PHP stuff and should be able to handle it alright. :)
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