Katherine reviewed the original TrackStick GPS, but now the company has come out with the improved Pro, with 4 times the memory.

What is it? A tiny GPS recorder which, unlike real time tracking devices, records histories; it doesn't tell you where you are but where you've been. For example, it could tell you where your kids have been, verify employee driving routes, and watch large shipment routes.

How does it work? The Track Stick receives signals from twenty-four satellites orbiting the earth. With this information, the Track Stick can precisely calculate its own position anywhere on the planet to within fifteen meters. That's comforting.

When I asked the inventor, Richard Haberkern, why he came up with the Trackstick, he explained that he was intrigued with the new GPS systems years ago and came up with Trackstick as a low cost alternative for individuals and was surprised when it was snapped up by the FBI, CIA and Homeland Security.

Since it's designed to work with Google Earth, it ended up being a very useful tool in Katrina, used for evacuation route planning, and is now being added to most search and rescue teams for mapping purposes.

It's powered by a cigarette lighter, or hard wired, or how shall we say -- covertly installed.

For more information, check out the site, Trackstick. And keep in mind, it is illegal to track someone without their permission!