The one on the right hides a USB port 2.0, a microSD card slot, and a 3.5mm headphone jack.

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And still other ghosts could return, one day, to save our hides.

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Another has shown a way of flushing the virus out of one of the tissues where it hides from the existing drugs.

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But one security researcher has revealed a tool that hides users in a less innocent guise: An unwitting victim's browser.

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The smallest one, the Reserve, is a 700 milliamp battery that fits on a keychain and hides its 30-pin connector under a flip cap reminiscent of a Zippo lighter.

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