Keeping close tabs on your faithful four-footed wanderer

When he's wearing the latest in doggy hi-tech bling, a GPS locater.

The satellite-linked devices, which have found their way to cars, big rigs, boats and even bicycles, are now available for the canine set.

Two companies are making collar-attached models that send a warning if a dog leaves its designated area. The gizmos then gives the animal's location, allowing you to find it without driving endlessly around the neighborhood, shouting its name.

In theory, it's a cool idea. In practice, neither of the devices -- Pocketfinder or Zoombak -- is quite ready for puppy prime time. And both are rather expensive because of monthly fees.

But as anyone who has lost a dog can tell you, it's an intriguing use of digital tech.

Here's a look at the two products, based on real-life dog tests.

Pocketfinder

Location Based Technologies is taking pre-orders for its product, which is in the final stages of development. Executives at the Anaheim company say they're confident they'll be able to start shipping it this summer.

But here's hoping that they'll take their time and wait until all of the bugs in the product are ironed out and that it's made easier to use. Based on the prototype that was tested, Pocketfinder is potentially an exceptionally cool gadget for dogs with wanderlust.

It works this way:

The owner activates the device, which is attached to the pet's collar, via Pocketfinder's website. This allows it to be digitally located, a trick it accomplishes not only through the global positioning system but also with use of the cellphone network.

The next step is setting a geographical boundary -- the area you want your unaccompanied dog to stay within. That could be a backyard or a field.

This was where the product really shines. To set the boundary, you use clearly marked aerial photo maps from Microsoft's excellent Virtual Earth platform.

For example, I was able to pinpoint my backyard, which is not at all spacious. Then I designated the yard as a "safety zone."

As long as the device was active, I got a cellphone text message and e-mail whenever my dog Earl left the yard.

However, this brought up a problem. I didn't get the message until Earl was out of the yard (safely on a leash and up the street for this test) for about four or five minutes. That amount of time can be crucial if you live near busy streets.