With this gear workers can gain access to their computer files and messages from any phone set in the company network.

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The MSN toolbar also comes with a desktop search application which indexes the contents of your local computer so you can find files and messages quickly.

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Great to look composed and completely on top of your assignments on the surface, but within the files lies several back and forth messages between yourself and several other parties.

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The Aimster software lets users search for and swap MP3 files instead of text messages.

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There is also some debate over a technique called steganography, which involves embedding secret messages within publicly available files and images on the internet, but there is little evidence so that al-Qaeda has used this.

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E-mails, text messages, photographs and other files relating to a particular person can all be accessed quickly through the phone's contact list, without switching laboriously from one application to another.

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These attempt to trick people into clicking on links and downloading booby-trapped files using cleverly crafted messages.

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In the March raid on Egypt's state security agency, Israa Abdel Fattah, a 32-year-old pro-democracy activist who had been jailed twice in the past three years, was shocked to discover in the agency's files copies of her emails, transcripts of phone calls and text messages, and a list of companies where she had applied for jobs.

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Attackers turn to such sites to glean information about individuals to help craft personal-sounding messages with booby-trapped files, which victims click on and unknowingly release malware into an organization, he says.

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