The big unsolved problem is scanner technology.

ECONOMIST: Bureaucracy not technology

So the problem is how to facilitate this, given that it is not practical to put them in a scanner every time someone wants to ask them a question.

ECONOMIST: Vegetative state

Hassan says he detected StarLogger on his machine with a rootkit scanner, deleted it, and later returned his laptop to the store where he bought it after experiencing a problem with a video driver.

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The problem with traditional barcodes is that when they are rendered on a smartphone, screen glare can prevent a scanner from reading them correctly.

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