Mr. Jubitz noticed drivers hanging around his stop after the usual meal and shower, hoping to find a load. So he decided to start signing up brokers and shippers who needed freight hauled from Portland. He listed the loads on a monitor at his truck stop and charged the drivers a nominal fee to get the phone number of the company wanting to move the freight. By the 1980's, DAT monitors could be found in hundreds of truck stops around the country, with 17,000 truck drivers and shippers subscribing.

''DAT is still the Microsoft of our industry,'' said Ken Hammond, the vice president for marketing for Getloaded.com, founded two years ago in Richmond, Va. ''But the Internet is changing things -- the monitor was, in effect, a monopoly. The Internet has allowed us to cut into that.''

DAT, while keeping its television monitors in place, has edged onto the Internet. It hopes to leverage that 17,000-subscription base into an online service called DAT Conexus (www.datconexus.com). The new service not only finds loads for truckers to haul, it also lists drivers and companies with extra rigs for use or rental.

DAT makes money from subscriber fees from truckers, freight brokers and shippers. Subscription prices vary depending on use and the size of the company. DAT also earns some revenue from online advertising for trucking supplies and used equipment.

Getloaded.com, on the other hand, charges truckers $35 a month for unlimited use of the Web loadboards, but shippers and brokers can list loads free.

''If a shipper can get on our boards for free and has to pay someone else, who do you think they will go to?'' Mr. Hammond said. ''In any case, we needed to develop a big database, and this is the way to do it. We couldn't have challenged DAT when it was the monitor loadboards, but with the Internet, the overhead just isn't there anymore.''

Mr. Hammond said Getloaded.com started making money this year, with 16,000 drivers or trucking companies subscribing for at least one month through the end of the year. But he said that he thought only a few companies would survive in the Internet load-matching market.