SEATTLE - Time Magazine calls the latest iPod "The 2006 Gadget of the Year." But some University of Washington grad students say a popular workout add-on could actually be used as a high-tech-stalking device.

The iPod isn't just music motivation for workouts. Apple now boasts that the latest gadget -- a partnership between Nike and Apple -- turns the iPod Nano into a workout coach; your personal trainer.

It's called the Nike + iPod Sport Kit.

A tiny sensor goes in your shoe, and through a receiver attached to the Nano, your shoes essentially talk to your Nano, churning out how fast you're moving, how far you've gone and how many calories you've burned.

"It's a really good product," says Scott Saponas, doctoral student in computer science and the lead author of "Devices That Tell On You: The Nike+iPod Sport Kit."

The UW graduate student is an avid runner who uses the latest gizmo, but he warns there may be a downside. He and a team of UW grad students say that during a research project, they uncovered a possible security flaw. He thinks stalkers could use the gadget as a tracking device.

"Our personal privacy is at stake," insist Saponas. The students discovered the tiny sensors emit a signal that can be picked up by any compatible receiver.

"If you were to set up a tracking station at multiple places on college campuses you could track where somebody goes," says Saponas.

They did it by connecting a receiver from the Nike + iPod to a laptop's serial port. When the sensor moves it emits a signal, that information is sent to a central server, which plots the sensor's location.

But it's not that simple: The potential stalker has to know the serial number on your sensor to track you, and the tracking range is limited. The receiver works with a 10 to 60 foot range.

Neither Nike nor Apple responded to our requests for comment.

The researchers sent their findings to both companies, but so far, neither has responded.

The grad students encourage users to turn off the kit when not using it so it stops emitting signals.

For More Information:

www.cs.Washington/edu.research/systems/privacy.html