(MONEY Magazine) – Talk about the computer revolution. today, one worker in 10 operates his or her own business from home. Moreover, those 14 million entrepreneurs, up from 11 million only five years ago, figure to be joined by 3 million more over the next three years. You could be one of the newcomers. All you need to get started is one of today's cheaper, faster, more adaptable home PCs. "Nearly 50% of home businesses in the '90s didn't exist 25 years ago," says Paul Edwards, co-author of Making Money with Your Computer at Home. "Computers are enabling people to work on their own cost-effectively."

There are now scores of home-based businesses you can start on your own computer after acquiring some basic training and specialized software. Money consulted more than a dozen home-business gurus and successful home-business veterans to come up with this list of four promising careers. These enterprises were chosen for their low initial investment (under $5,000), growth potential, reliable income and the limited training they require, which varies from as little as one month to two years. For further career suggestions and advice, see the source box at left.

-- MEDICAL TRANSCRIPTIONIST. As long as patients need doctors, there will be a demand for medical transcriptionists. How's that for job security! Furthermore, mere typists need not apply. To crack this field of more than 100,000 people, you'll need to develop an in-depth understanding of medical terminology to transcribe a doctor's dictated notes accurately. So you should plan on spending one to two years full time to get properly trained--longer if you study part time. Also assume you'll have a slow start. In this field especially, clients favor experienced pros. Once you've proved you're reliable, however, you can earn up to $70,000 a year.

Cynthia Ann Lewis, 53, of Salinas, Calif. turned to medical transcribing last year when her rising blood pressure forced her to leave a stressful job as a computer systems manager. Now, Lewis figures she'll earn more than $35,000 in her first year, and she's enthralled: "In this field, you learn something new every day." And six months into her new vocation, her blood pressure has fallen 30 points, to 110 over 90.

You'll need to spend $3,000 for a speedy PC with a 486 chip, a transcribing machine, word-processing software and a printer.

For more details: Rick Benzel's Health Service Businesses on Your Home-Based PC (McGraw-Hill, $14.95) explains how you can get started. MT Monthly (800-951-5559), an industry newsletter, also offers a correspondence course ($995).

-- SCOPIST. Those long paper strips produced by court stenographers record testimony in stenotype shorthand. Later, a computer program translates the strips into English, but skilled human hands and eyes must still check the documents for mistakes. That job falls to the nation's more than 800 so-called scopists, who edit the transcript with specialized software and return the final record to the court.

Cathy Vickio, 43, of Houston, took up scoping last year after burning out on secretarial work. To prepare, she took a correspondence course (see below), and within four months she was ready for business. She estimates a $30,000 income for her first year, though seasoned scopists can earn $40,000 annually.

To begin, you'll need a 486 or better PC and modem, plus scoping software--about $4,000.

For more details: Legal Services Institute has a correspondence course ($2,185; 813-531-2637). At Home Professions also provides correspondence courses ($867 to $2,050; 800-359-3455). National Court Reporters Association offers networking and educational opportunities ($90 a year; 800-272-6272).

-- BOOK INDEXER. In the first months of becoming an indexer, Matthew Spence, 44, of Middletown, Calif. couldn't stop categorizing: rooms of furniture, people, canned goods in the supermarket. Now, four years later, he's learned to turn off his mind after work. Still, to be a good indexer, he says, you must be meticulous. The nation's more than 1,000 indexers scan nonfiction manuscripts for key words and concepts, then input those into special software that sorts and arranges the information.

You'll need to take an indexing course (see the following page) and spend $3,000 for a 486 PC, indexing software, a fax modem and a printer. Spence initially found his publishing clients through relentless cold calling and now averages $50,000 a year. His tip: Specialize in order to get steady work at premium rates.

For more details: The American Society of Indexers ($50 a year; 512-749-4052). The United States Department of Agriculture Graduate School offers a basic correspondence course ($281; 202-720-7123).

-- MAILING-LIST SERVICE. "One of the easiest PC-based businesses to start at home is a mailing-list service," says Edwards. Such services compile customer mailing lists for local merchants or arrange bulk mailings for larger clients. You won't need formal training. A marketing background is helpful, though, and you must become completely versed in bulk-mail regulations. According to Direct Marketing magazine, mail-order sales reached almost $253 billion last year, up 8% from 1993.

Katie Allegato, 49, has been in the business 13 years, catering to hotels and retail establishments in the Orlando area where she lives. Although she works at lists only part time--10 to 15 hours a week--Allegato earns $30,000 annually. A full-time operator of a successful list business can rake in as much as $100,000 a year.

You'll need a 486 PC, a database program, mail-sorting software and a laser printer. Total cost: about $3,500. To begin, call anyone whose junk mail is either addressed by hand or carrying unnecessary first-class postage. That's how Allegato got launched.

For more details: How to Start and Profit from a Mailing List Service, a 90-minute audiotape from Here's How Products (Box 5091, Santa Monica, Calif. 90409; $22). Also useful: Mailing List Services on Your Home Based PC by Linda Rohrbough (McGraw-Hill, $14.95).

Home-based businesses offer an extra benefit: People are generally happier when they work at home. "You're able to do what you want whenever you want," says Lynn Walford, who is the author of Make Money with Your PC! "Working at home is self-empowering."

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