E-mail is subject to differing sets of protections when it is being typed, sent and stored.

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The law, which was overwhelmingly passed by Congress last year, makes it a crime to send junk e-mail using misleading subject lines or false return addresses.

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The new system will be modelled more on chat than traditional e-mail which means there will be no subject lines, cc or bcc fields.

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At first, I thought there was some sort of bug in Yahoo Mail that was causing it to grab subject lines from my spam folder, since many of the messages had that trying-too-hard quality found in spam.

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And rarely, if ever, can I get past the subject line in my e-mail inbox.

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The ads are selected to match the subject matter of the e-mail, with Google's ad-placement software picking up on certain key words.

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The list of contributors' e-mail addresses is handy for those who want to pursue a subject further.

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Mr Watson, who posts his daily thoughts on his own 'weblog', has been campaigning for Mr Blair to make an e-mail address available to the general public, and laid down Parliamentary questions on the subject last year.

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