There were demonstrations that allowed you to play music on headphones, test if products were genuine or counterfeit, or that let you replace your car keys or your house keys with just your phone.

WSJ: Is NFC Finally Becoming Mobile's Next Big Thing?

Go ahead and navigate to where your Atari 2600 ROMs are by using the mouse or the arrow keys on your keyboard.

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Sensors and microchips could be applied to your bag or jacket pocket and remind you to take your umbrella with you if the forecast is for rain or not to forget your house keys if you are leaving the house.

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You have to lend them your keys, or hide them somewhere.

WSJ: Is NFC Finally Becoming Mobile's Next Big Thing?

Sensors can tell you where your keys are, or who your dog likes.

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Security is handled through the phone or desktop app enabling you to share keys with your family as administrative users, normal users, one-off entry or even scheduled access.

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This tiny Bluetooth 2.1 controller is actually a jack of all trades device as it will control your phone, tablet or PC for gaming, multimedia control, remote camera trigger and even help find your keys -- via a free app -- if you lose them.

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These begin with the obvious, including never leaving your vehicle unlocked when parked, running unattended, sitting with the keys in the ignition or with valuables in plain sight.

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You can click on them with your mouse or finger, of course, but you can also use the left, right and Enter keys to select the one you want.

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