MeterPlug can cut power to whatever is jacked in as users wander away, and restore juice when they walk back into range.

ENGADGET: Insert Coin: MeterPlug estimates electricity costs per device, aims to save you some cash

With the help of Bluetooth, MeterPlug slings data to an Android or iOS app, and shoots updated meter information -- stored inside built-in memory -- as you come into range.

ENGADGET: Insert Coin: MeterPlug estimates electricity costs per device, aims to save you some cash

Yesterday, we told you about StickNFind, a nifty electronic sticker that lets you locate anything you tack it to, and MeterPlug, the smartphone-compatible power monitor with cost estimates and realtime consumption readouts.

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Decking out homes with smartphone-controlled appliances and using gadgets to keep tabs on electricity usage isn't exactly new, but the MeterPlug thinks it can do a better job of tracking exactly how much dough your devices are burning in electricity.

ENGADGET: Insert Coin: MeterPlug estimates electricity costs per device, aims to save you some cash