Dozens of parked purple, blue and orange semi trucks simmered in the desert heat at the Flying J Travel Plaza. Inside is a trucker's paradise: $10 for the half-pound carne asada steak with all the trimmings, cold drinks and lounge with a big screen television.

But for a growing number of drivers, the most valuable luxury at the Flying J is the invisible Internet signal that can be found in the travel plaza's parking lot. With just an $80 wireless network card, a laptop and a password, truckers can spend hours surfing the Web, e-mailing friends and filing paperwork -- without ever having to leave their trucks.

Using the same technology found in cordless phones, wireless fidelity, or Wi-Fi, is quickly catching on in the most unexpected places -- from truck stops and RV trailer parks to fast-food restaurants. Even the Mall in Washington is getting Wi-Fi access.

The 3.5 million truck drivers on the road who a generation ago made citizens' band radios popular are again on the cutting edge.

"Truckers have always been a quiet leader in anything having to do with wireless communication," said Allan Meiusi, vice president of Truckstop.net, which provides the Internet access. "Everyone's so hot about GPS [global positioning system] now, but truckers started getting into that 14 years ago. They were also the first ones to grab on to cell phones."

For the past two months, Truckstop.net has been advertising at truck stops across the country, and more than 10,000 subscribers have signed up since service began in October.

Hundreds of Truckstop.net hot spots are already in place at truck stops and travel plazas across the country and Canada. Thousands more are in the works. The company hopes to open 3,000 locations in the next two years.

With rates as low as $16.66 a month, drivers loyal to the Flying J can find Wi-Fi technology from St. Lucie, Fla., to Post Falls, Idaho. There are 148 Flying J hot spots out there, with more to come.

Sitting in his cab in the parking lot of the Flying J here, Ron Hasse opens his Hewlett-Packard laptop and logs on to the wireless network. Hasse, who owns his own truck, spends his time searching for his next load. Unlike company drivers who are paid by the mile whether or not they are carrying a full load, Hasse is not making money if his truck is empty. So the search is on as he cruises from site to site looking for the highest-paying customer.

Hasse is a minimalist's dream. His truck is his home, office and entertainment center. "I've got my laptop, a refrigerator, a microwave, a TV, a VCR and a DVD player all right here," said Hasse, who spends 11 months a year on the road, waving his hand toward the back of the cab.

Accessing the World Wide Web used to mean lugging his laptop out of the truck and into a truck stop, searching for a pay phone jack to dial up or waiting in line to use an Internet kiosk. Now for $200 a year, Hasse logs as many as five hours a day on the Internet, tending to the more mundane aspects of running his own business and entertaining himself -- as long as he's within range of a Flying J's Wi-Fi signal.

With so many hours spent on the highway, some drivers say they turn to the Internet to have some contact with the outside world -- away from CB radios, stale coffee and prepackaged sandwiches that sit in truck-stop display cases.

"It's more something to do. It breaks up the monotony, the boredom of driving," said David Moore, a driver from Kodak, Tenn. "You can chat with people, send e-mail. It's great."

But the Internet is also a valuable business tool -- giving drivers an inexpensive and convenient way to keep in touch with their dispatchers, pay their bills, do their online banking, file permits and check road and weather conditions -- without having someone peek over their shoulder in a truck-stop telephone room.

Internet access also allows drivers to check diesel prices as they plan their cross-country trips. Priscilla Sprenger checks Web sites that list the current diesel gas prices every night, allowing her to plan her route to avoid the more expensive pumps.

"It makes planning your trip so much easier. You can check the roads, fuel prices and stuff like that. But fuel prices are the most important," Sprenger said.

The 29-year-old Tulsa native first came across the wireless connection world after seeing an advertisement at a Flying J. Once she tried it, she was hooked. She even uses her PDA to access the network when she's not carrying her laptop with her.

"I have a cell phone, too, but the Internet is so much easier. And it's cheaper," Sprenger said. "Everyone is starting to do it."

David Maloney of Aledo, Tex., goes online from his truck using wireless fidelity at Flying J Travel Plaza in Waddy, Ky.