Business owners touted promotions Wednesday aimed at cashing in on the upcoming closure of part of heavily traveled Interstate 405, while city officials sought to assure the public that they were ready for the effects of a possible traffic nightmare during what's being dubbed "Carmageddon" in freeway-dependent Southern California.

Beginning Friday evening, authorities will begin shutting down a 10-mile segment of the freeway for 53 hours so crews can demolish one side of the Mulholland Drive Bridge as part of a $1 billion highway improvement project. The 405 freeway is a vital artery that carries heavy commuter traffic between the west side of Los Angeles and the San Fernando Valley as well as long-distance travelers from a web of interconnecting highways across the state.

At the Sherman Oaks Galleria mall, located next to a junction that will mark the northern point of the closure, mall owners touted an "I Survived Carmageddon Weekend Celebration."

Mayor Antonio Villaraigosa held a news conference at the mall Wednesday, to tell residents to turn traffic lemons into commercial lemonade.

"We need every Angeleno to chip in and turn this 'carmageddon' into a unique opportunity to explore local small business, neighborhood, and use public transport," said Villaraigosa.

County Supervisor Zev Yaroslavsky echoed the mayor's recommendation to stay out of cars and shop locally, adding that the weekend's outcome is in the hands of motorists now.

"The surface streets of this area and the feeder freeways for this freeway do not have the capacity to absorb half a million cars on the roads this weekend," said Yaroslavsky, referring to the typical number of drivers on Interstate 405.

"It's now up to the people, up to the motoring public of L.A. county, to make all the planning that's gone on work."

Restaurants at the mall offered two-for-one drinks promotions, free food samples and other incentives to lure neighborhood customers who may otherwise have been scared off the roads by a drumbeat of apocalyptic warnings from authorities.

"It's a very good business opportunity," said mall property manager Ashley Nazarian. "It's business as usual, if not better."

The 405 will be shut down the entire weekend between two key east-west freeways, the 101 and the 10. The freeway is viewed as one of the area's worst at the best of times, with traffic rarely moving faster than a crawl in many areas.

More than a month ago, officials started warning drivers to stay away at all costs. They planned a news conference Wednesday evening to outline some measures to ease effects of the closure.

City officials will open an emergency operations center on Friday and begin shutting down on-ramps at 7 p.m., followed by a full closure of the segment at midnight.

Larger companies, too, were taking advantage of the panic surrounding the closure.

In three hours, JetBlue sold out four Saturday flights between Long Beach Airport and Bob Hope Airport in Burbank, calling the service a "planepool" between the San Fernando Valley and the beach. Regular seats were snapped up for $4 and seats with extra legroom went for $5 for the 35-minute flight.

Several companies are also offering helicopter "taxis" that will allow commuters to leapfrog the epic congestion and arrive at Los Angeles International Airport on time for flights.

Two cinemas near the freeway will reward customers who brave the traffic with free popcorn and Redbox, which rents DVDs and games through vending machines, is offering Los Angeles customers 50-cents off select title rentals "to ease the pain" of the closure.

Outside Los Angeles, a hotel at Mammoth Mountain offered an "Escape Carmaggedon" package of a three-night stay for $405, plus tax.

With nonstop media coverage, roadside billboards warning of big delays and a stream of press conferences admonishing drivers to avoid unnecessary journeys, it has been hard to avoid word of the upcoming closure.

The Los Angeles Police Department even asked celebrities to use Twitter to warn their followers.

"This weekend, LA! Avoid Carmageddon, Gas-zilla, 405-enstein, Grid-lock-apalooza! STAY HOME. Eat & shop local!" Tom Hanks tweeted Wednesday.

For some residents, the city is overdoing it.

"I don't know what the big deal is, it's not like the freeways haven't closed before," San Fernando Valley resident Cheryl Robinson said. "When we've had earthquakes, people still get around."

Many recalled similar predictions of traffic doom around the time of the Los Angeles Olympics in 1984. Ultimately, circulation stayed light.

"I think it's going to be the city's best traffic weekend since the Olympics," said Merlin Camozzi, a lawyer who lives on the city's east side.

Steve Brill, a logistics planner for the film industry, said he and his wife had pledged not to get in their cars this weekend. Instead, they will ride their bicycles everywhere.

"Either it's going to be a frickin' nightmare," Brill said. "Or it's going to be a nonevent."