You've recently upgraded your old CRT monitor to a sleek new LCD and don't know what to do with that relic. Don't be in such a hurry to push it aside, but rather put it to use and double your computing real estate.

There's nothing like having two screens on your desk, giving you twice the viewing space. Not only does the mouse travel effortlessly from one screen to the other, but you can drag and drop folders across the border as well. I use one for my Windows desktop and the other for whatever I'm working on. It is easy and relatively inexpensive to hook up.

You'll need either a second video card or one with dual video ports. A single port card can cost as little as $20 and as much as $500. You only need the low-end type. The rest have lots of memory and cooling fans on board and are used primarily by gamers. Some have TV tuners and remotes and are also expensive.

The dual-port cards usually have a VGA port (analog) for your old CRT monitor and a DVI port (digital) for the LCD monitor. If you have two VGA's, you'll need a $10 adapter to make it fit. You can get a dual-port card for about $50-$60. Look online at tigertdirect.com or newegg.com for the best deals. Don't bother looking locally; you won't find any. I tried.

Know what type of video card your computer uses. They can go into PCI, PCI Express or AGP slots on your motherboard. The cards are specific and are not interchangeable, so make sure you get the right type.

Keep in mind, unless you have identical monitors, you won't have identical displays. The color will be a bit off a bit from screen to screen, but you can tweak the settings somewhat. Depending on your card, you should be able to adjust color, brightness, contrast and the gamma settings. As long as the sizes are similar, you'll be fine.

The resolution can be matched so the items on the desktops are the same size on each monitor. If one is set at 1024 x 768 for example, the other should be as well. Otherwise, when you drag an icon or open window from one side to the other, the sizes will be different. In some cases you may not be able to see an entire window.

Right-click on a blank area of your desktop and then click on Properties. Then go to the Settings tab where you'll be able to change the resolution. Once you have two monitors hooked up, you'll see a pull down menu with each monitor listed in the settings area. If only one is showing, then you're missing a device driver for a monitor.

If you don't have a disc with the driver on it, you can download it from the manufacturer's Web site. Alternatively, there are programs that can do that for you, but that's another column.

You'll see a small graphic of the two screens and a button that says Identify on that settings page. When you click Identify, a large 1 and 2 will appear on your screens respectively. If you need to swap them so the mouse is able to traverse the border, just drag the image of one screen on the graphic to the other side and click Apply.

You'll be asked to choose one of the monitors as your main desktop. It sounds more difficult than it is. Once you play with it for a while, you'll get the hang of it.

If you don't yet have a second monitor, perhaps now's the time. Prices have dropped considerably. For less than $275 you can get a 22-inch LCD just about anywhere. And you don't have to stop at two.

here are racks on the market that mount the LCD monitors. You can have them side by side or one on top of another. Have your office look like NASA and do a quad setup.

I have two computers hooked up to three screens. I use what is called a KVM switch (keyboard, video, monitor) to toggle one screen between two computers. They both use the same mouse and keyboard and are controlled by a switch on the device.

It is easier to work when you're able to spread out, and that's what having more than one monitor can do for you. Working on the Internet, this allows you to have more browsers open at the same time.

Whether photo editing or document editing, you can place the original on one screen and the one you're manipulating on the other. No more shuffling from one window to the next. There's room for them all to be open.

Once you've tried a dual-screen setup, there's no turning back.

Arthur Glazer is a freelance writer and computer technician in Gainesville. His column appears biweekly. Arthur welcomes your computer questions and ideas for future columns.