But Facebook says it still places a cookie on the computer of anyone who visits the Facebook.com home page, even if the user isn't a member.

WSJ: 'Like' Button Follows Web Users

In November Facebook launched Social Ads, which sends ads to a user's pals when a member makes a purchase from a participating marketer's site.

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Facebook's original users, college students, have graduated but still use the site, drawing in their peers in the process: the average Facebook user is now over 30 and a member of the workforce.

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This task is so complicated that it requires an ISstaff member to register each end-user machine, says James Mascaro, network architect for Xcelerate, an e-business consultancy in Fort Lauderdale, Fla.

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Using a feature called Nextel Direct Connect, a user can link up with a friend, family member or co-worker over a link that allows only one of them to speak at a time.

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OpenTable asks each user to enter an e-mail address to become a member.

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Anyone who has been asked by a friend or family member to fix a slow PC understands the average home user will happily click any link, accept any friend invitation, and even install software from just about any Web site.

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Under the new rules, pre-approval offers by mail to anyone under 25 is no longer allowed, students--and anyone else under the age of 21--must prove they have sufficient income to pay off credit card debt they incur, have a parent or family member co-sign their credit card contract or be added as an authorized user on a parent's credit card rather than opening their own.

WSJ: Students Still Targets of Credit-Card Offers

"Digital certificates are required for connection to the RRP service, but user ID and passwords are required to initiate a session, " explains Rick Wesson, an IETF member and a senior software engineer at Alice's Registry Tools.

CNN: Is domain name system vulnerable to slamming?

For example, messages from a spouse or close family member may get ranked ahead of promotional e-mails from a web-based service the Gmail user signed up for.

CNN: Gmail looks to clear clutter with Priority Inbox

This article is by Larry Drebes, a founding member of the non-profit OpenID Foundation and the chief executive of Janrain, a provider of user management solutions for the social web.

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