I hate to say it, but I think X10.com's ``spy cams'' can be useful for families with children or others who need to be monitored.

I do have a hesitation but it doesn't come from the products themselves. It's the way they're advertised. It's almost impossible to surf the Web without stumbling on obnoxious X10 ads.

They're horrendous for two reasons -- they pop under Web pages you visit and clutter up your screen. Even worse, many of the ads feature seductively posed women, as if to imply that the technology should be used for voyeurism. Fellow tech columnist Mike Langberg refuses to review X10 products because of his strong opposition to their advertising policy.

I respect Langberg's position but won't go quite that far because, despite the awful ads, these products are affordable and, for some families, very useful.

The company must have heard the complaints. It now provides a way to block the ads. X10's Web site offers a ``cookie'' that will prevent the ads for the next 30 days. You can download yours at www.x10.com/x10ads.htm. PanicWare (www.popupstopper.net) offers free software that will block X10 and other popup and pop-under ads.

X10 has numerous models and packages which makes locating the right product from the company's Web site (www.x10.com) a bit complicated. But once the camera arrives, it's surprisingly easy to install and configure.

All of the models are built around a small inexpensive video camera that can be mounted on an inside or outside wall or even perched on a table. Each transmits signals through the air at 2.4 GHz, which is the same frequency used by some cordless phones as well as the increasingly popular 802.11b wireless local area networks. I was warned that my wireless LAN might interfere with the X10 cameras, but I didn't have any problems.

The device has two primary uses. It can be a security camera and it can be used to check in on young children or convalescing adults who want to be monitored. A friend of mine uses his camera to keep an eye on his elderly father who suffers from Alzheimer's disease.

The basic $80 XCam2 kit consists of a camera and a receiver. The camera plugs into a power outlet and the receiver plugs into an RCA input jack on a TV anywhere in the house. If your TV doesn't have an RCA jack, you can connect it through your VCR. For $129 you can buy a version that also lets you connect to the USB port of a Windows PC. Mac users are out of luck.

The basic unit has a 60-degree viewing angle which should be adequate for settings where the person being monitored is in a crib or in bed. For an extra $20 you can get a ``wide eye'' model with 120-degree view.

Another option is the $169 ``Ninja Pan n Tilt'' kit that lets you remotely move the position of the camera to monitor different parts of the area. It comes with a wireless remote control that uses radio waves (not infrared) so it doesn't have to be in the same room as the camera.

The company also offers software that allows you to transmit the images via the Internet so you monitor the house from anywhere in the world. The Ninja product can be controlled via the Web (with password protection), letting you pan and tilt the camera remotely. This feature isn't useful when taking care of kids (one needs to be close), but it could be useful for security purposes or if you have an elderly relative who lives alone but wants to be looked in on. Don't expect TV quality or full motion video over the Internet. Movement will be choppy, even if you have a broadband connection on both ends.

X10's remote products assume that the remote location has both a PC that's always on along with a persistent broadband Internet connection such as DSL or cable modem. Panasonic makes the much more expensive ($499) KX-HCM10 Network Camera, which has its own Ethernet connector and does not require a PC though it still requires a broadband connection.

The standard equipment transmits video only, but X10 offers optional versions that will also send an audio signal. Before investing in a video system like X10, consider whether audio will do the job. Fisher Price makes a $19.99 ``Sounds 'n Lights'' baby monitor that not only transmits sounds, but lights up when baby makes noise. Unlike a video solution, you can carry the receiver in your pocket as you walk around the house.

Before installing any wireless equipment, it's important to be aware of security and privacy risks. The New York Times reported that security experts (and hackers) can intercept X10 signals from more than a quarter mile away using $250 worth of off-the-shelf equipment.