Today, couch potatoes can have so much more, for example, touch-screen consoles that control your home's lights, TVs, window shades, room temperatures, security system, sound system and even the front door.

It's part of what the electronics industry calls a "smart home" because you can program certain electronic functions, including via computers and other electronic devices while you're away from home.

Smart homes are one of the big themes at this year's three-day Electronic House Expo, which started Thursday at the Orange County Convention Center. The show, featuring 325 manufacturers' exhibits, is expected to draw nearly 11,000 electronics retailers and other businesspeople.

The event is not open to the general public.

"You're not just selling them components and equipment. You're selling them a lifestyle," Paul Williams, vice president of service for Control 4, a Salt Lake City firm that makes home automation equipment, said during a presentation.

"It's all about comfort and convenience," said Jason Sherrill, product manager for Houston-based Cooper Industries' home-automation business.

The burgeoning trend toward home automation is not just about helping people with disposable income find new ways to be lazy.

The systems have practical uses, exhibitors say.

• If you're out at night, wouldn't it be safer to turn on the lights at home before you get there?

• If you're a parent at work, wouldn't it be good to disable the TVs in the house to make sure your kids do their homework?

• If you're on a tight budget, wouldn't it help to adjust the air conditioning in different rooms to save energy?

Speaking of budgets, equipping your home to be "smart" will cost you a few hundred dollars to more than $10,000, depending the size of your home and the number of options in your system.

The middle class is buying into the smart home concept that was once strictly for the wealthy, said Manuel Quintanilla. Quintanilla is the owner of E-Home Solutions in McAllen, Texas, which installs home-automation equipment and other electronics.

Quintanilla, a show attendee, used to work for electronics retail giant Best Buy on the Geek Squad, a 24-hour computer support task force that makes house calls. He said he knew the market for such services was growing, so he spun off a similar business for himself.

The systems on display are meant to be financially accessible to many households, exhibitors said.

But they seem basic compared with some of the high-concept systems that are being developed.

At its headquarters in Redmond, Wash., Microsoft Corp. has set up a "home of the future" in which some of the company's software capabilities are embedded into everyday items.

The front door unlocks by identifying your palm print. The screen on the wall reveals the whereabouts of your spouse or children. The house talks back to you if some instruction while cooking or doing the chores is needed. There's even a bedroom mirror that suggests clothes to help you match an outfit.

Exceptional Innovation, a Columbus, Ohio, firm, created its own scaled-down version of the Microsoft house at the show.

"We don't make the TVs and the DVD players, but we make the software that integrates with it," said Jason Brown, one of the firm's technical support specialists.