These storehouses of information -- where a user can make deposits or withdrawals -- eventually may have the same impact as the printing press. Although there are only about 3,000 bulletin boards currently in existence in the United States (more than 5 million personal computers have been sold in this country to date), future uses seem endless:

Imagine coming home to check the screen, not the mailbox, for your electronic mail, both text and voice. Communication could be instantaneous -- and cheaper than the Postal Service. Junk mail could be sent to oblivion with a jab of the index finger.

Directory assistance: Forget about letting your fingers do the walking once every phone number in the nation is on a bulletin board for instant access.

Preparing to travel? Get all your information -- schedules, hotel accommodations, rental cars -- from a travel services board.

Gone will be the days of writing a stack of checks to pay bills. A simple "yes" into your bank's computer and your previously entered list of scheduled payments is made by electronic funds transferred to your creditors' accounts.

In many cases, the future is now. A few local bulletin boards already have sprung up to serve a variety of needs and interests:

Remote Bulletin Board System: Operated by Tom Mack, a General Electric Co. employe and the president of the Capital PC User Group, this board is devoted to philosophy and religion. Recently, its community of users was put to the test when someone posted a suicide notice on Mack's board -- the electronic equivalent of a man on a building ledge. Users immediately responded with messages of reassurance, insight and moral discourse.

River Watch: Mike Arnold of Fort Washington, Md., the controller for the Immigration and Naturalization Service, started this board to provide a communications channel for people with a special interest in using and protecting the Potomac River. Arnold, who lives and sails on the river, provides information on tides, wildlife, fishing, water quality, recreational facilities and development issues.

Neighborhood Watch: The Fairfax County Police Department, as part of its crime prevention program, started this board on a pilot basis. Civilian Neighborhood Watch coordinators are provided program information and helpful hints on how to combat burglars and other crime, much like the traditional newsletter. When new crime patterns develop, they are disseminated instantly, and the coordinators can exchange information.

Bullet 'n Board: Run by Tanya Metaksa, a Springfield, Va., computer and political consultant, the antigun- control board posts legislative and other information on gun control issues, pushes one point of view, but also hosts debate in messages exchanged by its participants.

HomeInform: Wheaton Plaza and Tysons Corner shopping centers have boards listing current movies and showtimes. The board also lists merchants, gift ideas for shoppers, special sales and events.

According to Wheaton Plaza spokeswoman Kim Maurey, expansion of the HomeInform board is being considered. One option is an electronic catalogue.

Although some boards have commercial goals, most are operated by individuals for social and educational reasons -- and to put their expensive computer equipment to use during the 23 hours of the day when it would be idle anyway. Many have evolved in response to the high-price structure of the software industry: Participants, for instance, can exchange, for free, public domain software.

Kim Wells runs one of the area's "techie" boards, specializing in ham radio. His board has been a way for him to become current in computer technology and software, and to provide a public service in software and message exchange among technically oriented people.

David Purks and Rudy Parsons run a board that is one of the area's best storehouses of useful and up-to-date computer programs. On it you can find a free word processor, dozens of powerful utilities, a spelling checker, financial programs and spreadsheet templates, games, news articles, an electronic mail service, and even software to start your own bulletin board.

Electronic bulletin boards also are effective problem-solving tools. Rather than spending time researching a technical problem, one can rely on the participants' expertise: Just post the question on a board, directed to no one in particular, and wait a day or two.

Almost always, there's an expert out there who posts a reply that is specific and helpful. And free.

As in every revolution, there is a down side. Demand for access is high, far beyond the capacity of unpaid board operators to provide. The cost of board equipment, maintenance, quality control and organization is real. Few are willing to pay for access now, and until the end-user-pays barrier is broken, supply will not expand to meet demand.

Some board operators have crossed ethical and legal boundaries by posting copyrighted material and software. Racism and pornography are promoted on some boards.

Boards also have attracted destructive personalities. A few files called "worms" or "trojan horses" have appeared. They have the appearance of useful software programs, but they are deliberately designed to be destructive. Such a trojan horse might work correctly the first 99 times to give someone, for instance, the zip codes he needs for certain cities; and then, on the 100th request, wipe clear the memory of the computer and all disk information currently installed -- months of work wiped out in milliseconds.

And the case of California bulletin board operator Tom Tcimpidis had a chilling effective on many prospective operators. Unknown to him, someone posted unauthorized telephone credit card numbers on Tcimpidis' board, from which they were widely dispersed. The police showed up to arrest him one day, and to confiscate his equipment. The prosecutor's legal claim, since dropped, was that the bulletin board operator was violating law by "publishing" confidential information.

Incidents such as these aren't going to stop bulletin boards from proliferating, however. In the meantime, it's educational (and fun) to poke around a bit on some of the bulletin boards in the Washington area, and get a glimpse of the leading edge of the new information age.