Blake and Steve Pollack love traffic jams.

When there's traffic, people can't help but stare at the advertisements that the Pollacks mount on the sides and backs of big rigs. The trucks slog up and down Southern California freeways in the mornings, when the traffic is bad, and travel over surface streets during the day, making more traffic as they try to navigate sharp right turns and hills.

"You can't ignore these ads," said Blake Pollack, the younger half of the father-son partnership behind Mobile Vision Marketing Inc., a Culver City, Calif.-based company hoping to thrive off renewed interest in outdoor advertising.

As consumers look for ways to avoid traditional ads on television and radio, the medium is growing. In 2005, billboards and other outdoor ads raked in $6.3 billion and have become the fastest-growing advertising form after the Internet, according to the Outdoor Advertising Association of America.

Companies that want a good return on their advertising investment like the idea that consumers can't click off or fast-forward through outdoor ads, said Stephen Freitas, spokesman for the industry group.

"It's a medium that isn't controlled by consumers," he said. "You can't zap it or TiVo it."

Increasingly clogged roads also lead to more eyeball time on outdoor ads. Nationally, the average commute time to work each day is 25.5 minutes, up three minutes from a decade earlier, the latest census data show.

GROWING BUSINESS

As a result, more and more companies are opting for messages that inch along with their traffic-jam-trapped targets, the outdoor ad group said. Transportation-based advertising — posted on cars, trucks, trains or buses or displayed in airports and at transit stations — accounts for nearly 20 percent of outdoor ad revenue.

The Pollacks, who started their business in March, are concentrating on Los Angeles, where people spend an average of 28.9 minutes traveling to work, according to the Southern California Association of Governments.

It's the perfect business venture for the Pollacks. Steve, 58, who owned a textile company for more than 20 years, is familiar with the printing side of the business. And Blake, 24, who worked in the film business before starting the company, says he brings creativity to the table.

FOLLOW THE DRIVER

Mobile Vision Marketing leases trucks and outfits them with global positioning systems to follow the drivers' routes. Clients then choose whether they want to use an empty truck and tailor the route to a targeted audience or, for less money, put ads on the sides of trucks that run pre-scheduled delivery routes.

Clients pay about $3,500 for a four-week campaign to put their ads on delivery trucks running their normal routes and as much as $25,000 for dedicated trucks, which give clients control of the route. The Pollacks contend that this is a much better investment than a billboard on, say, Sunset Boulevard, which costs more and stays put. The more expensive option is comparable to the cost of a radio advertising campaign or ads on city buses, according to the company.

"It's like a mobile billboard,'' said Celessa Batchan, marketing director of radio station KRBV-FM in Los Angeles, which used a Mobile Vision gasoline tanker to advertise a free-gas promotion.

That a radio station, once the go-to place for advertisers, looked to an outdoor advertising company because it could reach a more targeted demographic highlights the lure of the movable message.

But not everyone is enamored with the idea of advertisements traveling the crowded streets of Los Angeles. Standing billboards have long been controversial. A 2002 city ordinance to limit the number of billboards sparked lawsuits from outdoor advertising companies. The resulting settlements were opposed by local activists, who contend that the deals would allow signs to proliferate.

ADVERTISING BAN

"There is a battle right now for the eyeballs of the American people,'' said Kevin Fry, president of Scenic America, a Washington-based organization that sees billboards as visual blight. "How much of the public realm do we want to turn over to advertising?"

Hawai'i, Alaska, Maine and Vermont have banned billboards, and some local governments around the country have moved to limit or outlaw the signs.