E-mail Tracking Device

Who Got the Message? There’s a Way to Know http://www.nytimes.com/2004/06/03/technology/circuits/03spyy.html

A new service promises to pull back the curtain on anyone hiding behind the common white lie "I never got your e-mail." Users of the service, DidTheyReadIt (didtheyreadit.com), can clandestinely track when and where their e-mail is read.

The service, which has already drawn complaints from privacy advocates, offers a new and quiet way to harvest behavioral information about friends, colleagues and potential consumers.

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Subscribers to the DidTheyReadIt service receive an e-mail message notifying them of the time, rough location and duration of the the recipient's viewing of each message the subscriber sent. The service is available in quarterly, semiannual or annual subscriptions and ranges in price from $25 for three months to $50 a year. A free account allows users to send five tracked messages a month.