CAPTCHAs are commonly used for user registration, contact forms, or failed logins.

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The system also provides a mechanism for a user to selectively establish contact relationships or connections with other users, and to grant permissions for such other users to view personal information of the user.

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The true promise of Google Talk --and the company's likely goal--is to eventually provide full telephone capabilities, and to make a user's Gmail address their primary point of contact, on or offline.

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The true promise of Google Talk--and the company's likely goal--is to eventually provide full telephone capabilities and to make a user's Google login his primary point of contact, on- or offline.

FORBES: Magazine Article