This column usually deals with computing tips, but allow me to deviate somewhat from that course for the moment. And that is exactly what I want to discuss: deviating from the course, or trying not to with the aid of GPS or Global Positioning System devices.

We may not yet be able to beam ourselves across town, but now we can listen to the advice of our cars, with the assistance of GPS units on how to get there.

Just like all electronics, GPS prices have become affordable now that they have been available for a few years. You can still spend upwards of $1,000 for one with all the bells and whistles, but some basic models can be had for as little as $200. Many new model cars have these devices integrated into the dashboard, while less expensive after-market GPS units adhere to the windshield with a suction cup.

Designed for military use by the Department of Defense back in the 1980s, Global Positioning has 24 solar-powered satellites in Earth orbit. Once your device gets a reading from a handful of the satellites, they can pinpoint your position within a few feet, track your speed, determine longitude and latitude and even your altitude.

There are vast differences between models, so if you are shopping for one, caveat emptor. Most will speak to you, some more specifically than others. The lesser models will say, "Turn left in a quarter of a mile." The better ones tell you, "Turn left on State Road 13 in a quarter of a mile."

The difference is important if you're in a strange town with lots of roads at that intersect. The really good models even accept voice commands. For example, you could ask it, "Where is Green Street," or "Where is Chevron Gas" and get directions to them from your current position.

Some GPS will advise you to traffic conditions, offering alternative routes. With my Magellan Roadmate, it's an extra charge. That's not the case with the Navigon 5100 and 7100 series. It's included for life, according to their Web site. They also offer some of the best graphics out there.

Some GPS units allow free map updates via the Internet, as Tom Tom does. My Magellan offers the updates, but they charge dearly for them.

Higher end units incorporate Bluetooth technology so you can answer your Bluetooth-enabled cell phone through your GPS device, hands-free.

There are also differences in POIs or Points of Interest such as gas stations, motels or restaurants. They vary from a few hundred thousand to a few million. Some allow you to add your own POIs and personalize your map database via included software and your computer.

Many of the office supply and electronics stores have various models to choose from, but don't depend on the sales help for the best advice. Use the Internet to do some research. Many of the same stores sell GPS online and allow reader feedback on items purchased.

See what consumers and editors have to say. They may help to sway your opinion of a device. Watch to see if the mounts, power adapters and cases are included in the price or if they are extra. Do they include an MP3 player, a photo viewer and Bluetooth capability, and are these necessary?

Also look around at sites such as overstock.com, tigerdirect.com and newegg.com where you can save a bit by getting last year's technology or a refurbished item. If you don't need state-of-the-art, check it out.

The accuracy and ease of the GPS astounds me. Sure, there are mistakes and there is more than one way to reach a destination, but for the most part they have changed the way we drive. Just as you don't leave home without your cell phone now, you soon won't take a journey without your GPS. It guarantees not just a more accurate trip, but more pleasant one as well.

Guys, that means no more wrestling with roadmaps, trying to refold them. And ladies, no more wrestling with your significant others about whether they should ask for directions, or heaven forbid, turn the car around.

Arthur Glazer is a local freelance writer and a certified computer technician.