Adding monitors is just one way to gain added screen space, of course. A monitor with a 24-inch screen would offer about 50 percent more screen area than a single 19-inch model and would take up less desk space than two 19-inchers (less than two feet from side to side, versus about 33 inches for a pair of 19-inchers).

But for my applications, at least, the extra width of a two-screen array seems more useful than the extra height of a larger single screen. And where more height would be useful -- reading Web pages, for example -- some 19-inch and smaller screens can pivot from the normal "landscape" position to the more upright "portrait" mode.

Further, a pair of smaller screens will usually cost less than a single big one. While a 24-inch Dell "wide aspect" screen is now about $1,000, a pair of 19-inch Dells could cost as little as $550 -- about half that if you already had one 19-inch monitor, and even less if you found one of the many bargains available in displays that size. If you are willing to use a smaller monitor for your second display, you can save even more; 17-inch flat-panel monitors, for example, are often less than $200 each.

A pair of independent monitors just sitting side by side look functional but hardly stylish, and their separate bases occupy a lot of desk space. For about $200, you can attach two flat-panel monitors to a stand with a single pedestal, like those made by Ergotron, Mass Engineered Design, Zenview, 9X Media, Ladybug and DoubleSight. Stands that stack two monitors instead of placing them side by side are also available, as are models holding three or four displays.

Adding more monitor outputs to a computer is usually not difficult. For desktop PC's, you can either add a second graphics card (the board that links your computer to your monitor) or replace your single-output graphics card with a dual-output model (about $80 and up) -- and probably get other improvements (like faster screen response for games) in the bargain.

You can add more video cards if two screens are not enough and your computer has the slots to hold them, or buy triple and quad cards from Matrox and Nvidia. (Just make sure you get a card that fits your computer's graphics slot: PCI, AGP or PCI Express. Your computer's manual should tell you this, or you can run the system scanner software at www.crucial.com.)

If you have a laptop computer, or are reluctant to delve into your computer or hire a technician, you can use the Matrox DualHead2Go, or Tritton SEE2 adapters. The DualHead2Go ($169, shopmatrox.com) plugs into the VGA monitor output of laptops and some desktop computers; the SEE2 ($99, retailers listed at www.trittontechnologies.com) plugs into a U.S.B. 2.0 socket.

And that gives me an idea: Adding a second monitor turned out to be the easiest, most cost-effective and significant improvement in my work since I replaced my modem with high-speed cable. Now if I can just rig my laptop as a third screen hmmm.