You won't read this in the mainstream computer journals, but the Commodore Amiga, long regarded as just a gizmo for graphics and games, should now be considered an alternative to the new IBM and Apple systems as a business computer.

The Amiga is capable of multitasking, that is, of running several programs at once. That means you can start a new document while you are printing another and, at the same time, transmitting it by modem. Or you can start working on a new spreadsheet while another is being recalculated. Or listen to computer-generated music while you work.

The Amiga can address as much as 9 megabytes of memory, enough to hold several large programs at once with room to spare. The most powerful IBM systems are only now acquiring such capability, and there is no application software to take advantage of it.

The new multitasking IBM operating software, OS/2, written by Microsoft, costs hundreds of dollars and will not run on standard PC or XT-class computers. It requires an AT-class machine or one of the more expensive IBM PS/2 models. That leaves an estimated 8 million PC or compatible users with the choice of buying a new computer and new operating software, or being left behind.

There are similar doings in the Apple world. The Macintosh now offers a measure of multitasking in its latest operating software, and it can address megabytes of memory. But color graphics are available only on the new Macintosh II, with prices beginning at about $4,000. That's four times the price of an Amiga 500 and twice the price of an Amiga 2000.

The Mac II's colors are sharply defined but not as rich as those of the Amiga, which can display 4,096 colors at once.

The Amiga offers an established operating system, in use since 1985. Like the Macintosh, it uses a mouse, pull-down menus and the point-and-click method of telling the computer what to do. There is also a command-line interface similar to that used on IBM systems.

While the Amiga is best known for graphics and sound, there is now an impressive selection of basic business software. Business programs for the Amiga rarely cost more than $200, about half the price of similar software for the IBM and Mac.

An exception at $395 is WordPerfect, the hottest-selling word processor in the IBM world, now available for the Amiga. It works keystroke-for-keystroke as it does on IBM systems.

There are a lot of simpler, less expensive word processors designed for the Amiga and notable for their ease of use. Commodore's Textcraft Plus lets you point and click your way through all the basic word-processing functions (no spell-checker, however). It can be learned quickly by anyone with even a rudimentary knowledge of writing on a computer.

There is no Lotus 1-2-3 spreadsheet for the Amiga but there is VIP Professional, which uses the same command structure and can read and write Lotus files. Other Amiga spreadsheets can handle Lotus files, but they use the mouse-and-menu interface more common to Amiga software.

Data-base software for the Amiga ranges from simple and inexpensive file managers to complex, more expensive relational data-base systems. There is also a wide selection of desktop-publishing programs for the Amiga that compare favorably with counterparts in both the IBM and Apple worlds.

Finally, for those who must have an IBM-compatible system, Commodore offers the Bridgeboard, a $695 enhancement for the Amiga 2000. It is a PC-compatible computer on a snap-in card with 512K of memory. It has its own 5 1/4 inch disk drive, but can also share the Amiga's disk drives, including a hard disk.

The Bridgeboard runs PC software with little trouble, but at 4.77 megahertz, it is slow by today's standards. The sharing of Amiga disk drives is accomplished by a bit of software magic that was not reliable with the hard-disk unit I tested. Files got lost. Once an entire directory disappeared.

Such bugs are not uncommon with new hardware and software, particularly something as tricky as getting two computers to exist in the same box. But lost files are intolerable, a risk no business can afford.

There are other drawbacks.

Because the Amiga display has no text mode, the computer must continually repaint the screen. Scrolling and paging through documents can be slow, especially with the Bridgeboard.

Text display on the Amiga is also fuzzy by today's standards, matching only the 640-by-200 pixel text of the early IBM color systems. The Amiga does much better displaying pictures, but that's because it can use so many colors.

Still, the Amiga offers most of the power of the new IBM and Apple systems at lower cost and with plenty of application software.

So why haven't you heard more about it?

Amiga users, dealers and software developers complained bitterly that Commodore has done a poor job of marketing the computer.

Commodore, they said, has refused to advertise it, which is why they think it has gotten little coverage. More on that in a future column.

Brit Hume is a contributor to the Washington Post Writers Group. Hume is an ABC News Capitol Hill correspondent and the founding editor of a computer newsletter.