When one of the two warring factions of the Satmar Hassidim was looking to advertise its annual commemoration of the late Grand Rebbe Joel Teitelbaum's escape from the Nazis, it decided to hire a pro. It is after dark when Dave Porter, a burly 38-year-old Irish American with a tuft of blond hair, pulls away from his home in Bergenfield, New Jersey, after dinner with his wife and daughter. Their house, just a kilometer from where Porter grew up in a solidly middle-class neighborhood, is just far enough from his father to keep a healthy distance, and many miles from where he spends his nights. While most people prepare for sleep, Porter's work is about to begin. He joins the city's late-night veterans - 24-hour deli clerks, prostitutes, panhandlers and police - with whom he cohabits in the shadows of the city. For a gentle man, who is delighted to spend the daylight hours at the mercy of his two-year-old daughter, his nighttime occupation, plastering the city with the latest ads and dodging the police, comes as a surprise even to him. "I never thought I would be doing this," says Porter, a former pharmaceutical company employee who has come to love the freedom of the street. "I feel like I'm flying by the seat of my pants." His first stop is a Bronx warehouse, where he loads his silver pick-up truck with three tubs of a biodegradable paste and a stack of posters, before making his way to Brooklyn, where he works through the early morning hours placing posters for movies, concerts, the newest gadgets and various causes on wooden barricades and sidewalk scaffolding at construction sites. Most are up and gone with the blink of an eye, washed away by the rain, and replaced with others hawking iPods, soft drinks, albums, cheap vacations. Long a part of the American landscape, the street posters carry a certain mystique. From the early days in the 1800s when merchants used walls and fences to notify passersby that their establishments up the road sold horse blankets, rheumatism pills and the like, sniping, or "wild posting" as it is known in the trade, has never been entirely above ground. The posters have been called an urban eyesore by some, and art by others. The men who put them up have been similarly eyed with suspicion. Some cops close their eyes, others fine them or throw them in jail. But to most, they remain invisible. THE FIRST LARGE American outdoor poster is generally attributed to Jared Bell, who printed 50-square-foot posters for a circus in 1835. In 1850, exterior advertising was first used on street railways. By the 1870s close to 300 small sign-painting and bill-posting companies existed. In 1900, a standardized billboard structure was created and ushered in a boom in national billboard campaigns. Confident that the same ad was easily transposable from Connecticut to Kansas, big advertisers like Palmolive, Kellogg and Coca-Cola began mass-producing billboards for the national market. By 1912, standardized outdoor service was at the disposal of national advertisers in nearly every major urban center. Though "wild posting" began as a cheap alternative to more mainstream advertising, today clients include high-profile companies like Sony, Nissan and Gap. The recent campaign by Apple featuring a silhouette listening to an iPod was the latest sign that wild posting is no longer just an underground alternative. The poster campaign, which reverberated throughout New York City, served as the cornerstone of the iPod campaign. High-profile companies use ad agencies who assume responsibility for the risks involved. "Hanging out on the streets of the West Village, the posters were always shrouded in mystery," Porter recalls, while driving through Brooklyn with a cigarette dangling from the side of his mouth."I never saw anyone put them up." Now Porter is doing just that. He has seen late-night robberies; been inches from a shooting; knows the ins and outs of panhandlers' routines; seen people get hit by cars and the "drunkest fools fall down." "We're kind of part of the street; we see everything," he says. IT'S A WEDNESDAY night and an early winter chill hangs over New York. Porter, dressed in a sweatshirt, jeans, a wool hat and worn-out loafers, keeps close tabs on the weather from his car radio - the slightest variation can put a kink in his night. If it falls below minus 7ÂºC, the antifreeze in the winter paste won't hold and the posters will fall. He drives around with an unlikely tool: a map of the Williamsburg eruv, the line that separates the haredi residents from the non-Jews in this divided neighborhood. The map, a recent addition, has helped Porter navigate the cultural divide. Broadway runs down the middle. "Mainstream posters go on one side of the avenue, religious posters on the other," he explains. In the summer of 2006 Porter's business took an interesting turn. Returning home late one night in June, Alexander Rapaport, who runs a haredi marketing firm, spotted Porter on the side of the road spreading glue on a fresh piece of plywood. He had seen his work on the streets of Williamsburg and saw in outdoor advertising the potential to fill a need in the haredi world in which advertising was limited to sect-driven newspapers. Posters offered a way to communicate across the divide, and Rapaport jumped at the opportunity. On his nights off from his regular job, Porter began working the other side of the avenue. And before he knew it, he was working almost as much for clients in haredi Brooklyn as for his regular job. "At a certain point I could have just about quit my job and worked only for the Orthodox," he says. When he first began, crowds of religious men would gather on the street to read the posters. "There was so much text, almost a book's worth," says Porter, who was used to posters that were flashier and not as text-heavy. Differences in the ads north and south of Broadway reflect two sets of neighbors who couldn't be more at odds. At the corner of Lee Avenue and Division Avenue, the posters are solemn and without graven images. Written mostly in Yiddish, they announce the annual Satmar fund-raiser that commemorates the day Grand Rebbe Joel Teitelbaum escaped the Nazis. Two sons, vying to become the next grand rebbe, have split the sect in two and for the second year in a row have held separate celebrations. Only a few blocks away, another plywood wall stands in stark contrast. Fluorescent colors advertising a new soft drink, Rambo the movie, the latest Chris Rock album, vie for pedestrian attention. But Porter rarely pays attention. "A poster is a poster. This poster says 'NY Piers,' otherwise I wouldn't have known which side is up or down," he says as he pastes the Yiddish Satmar ads on a piece of plywood. "It's been great to get to know a different culture," says Porter, who has learned about Shabbat, the Jewish holidays, mezuzot and the strict rules of modesty. In a few instances, he learned the hard way. Soon after posting racy posters of Jennifer Lopez on sites that fell within the Williamsburg eruv, Porter noticed they had been scratched out or torn down. Someone finally explained that such images were forbidden among religious Jews. "They get offended, so now I keep those posters north of Broadway," he says. But sometimes the offended cross the border. "There is a man with blue paint, I have yet to meet," says Porter, who found a recent campaign for Mary J Blige that features the singer baring her long slender legs, covered in splotches of blue paint. BUT TONIGHT, with 500 Satmar posters left to go and 48 hours till Shabbat, he runs into a different kind of trouble. A double run-in with the same policeman forces him to quit halfway through the job. "I've always had this rule - don't ever let a cop see you twice, then he has every right to get pissed." Keeping a low profile is part of the job. Technically construction site ads are illegal according to the New York City law. Still companies that engage in outdoor advertising often have agreements with construction site owners. They get permission, and sometimes rent space. The business is lucrative and many companies are willing to risk the penalties. Experts estimate that illegal ads can bring in $40,000 to $50,000 a month. Moreover, the city has no power to remove them, and enforcement is inconsistent. "If there are enough complaints to the police, they will crack down," says Porter. "It's like they say, shit rolls down hill." Porter carries permission slips obtained from owners in the dashboard of his car. But police don't always accept them as valid proof, and Porter doesn't entirely mind. He has a vested interest in keeping the work somewhat illegal. "The reason it pays well is the chance that on a wrong night you go to jail," says Porter, who spent one night in prison (and "passed" on the baloney sandwich). "The more it becomes legal, the more reason to pay less because there is less risk involved." Since September Porter has been back to his regular routine. He has had little opportunity to work south of Broadway. Eliezer Wise, also known as Lazer, a 23-year-old upstart who moved to Brooklyn from Israel, has nearly priced Porter out. At first the two rivals butted heads. Porter felt Lazer had encroached on his territory. But he quickly gave up. "For the price he is charging, I told clients they had to give him a try," he says. "I think we offer a different level of service, but sometimes if you just want to get the word out, you have to go with the lower price." Porter is known to use a stronger glue that can survive the rain for a longer time, and his work is so precise, with each edge carefully placed, it looks almost machine made. In Israel, religious neighborhoods are so tightly packed with posters the haredim joke that if it weren't for the thick layers, the walls of the buildings would fall down. Having spent four years postering in Israel, Lazer arrived on the Brooklyn scene with a few advantages. He was religious and cheap. "Putting up posters is the only way to advertise for frum people," he says. "The newspapers people buy on Friday and throw them out Sunday, but with me they get two weeks on a wall, so people see it." His Brooklyn-based company, Ad Now Advertising, does about 10 campaigns a week. "Dave had his customers, and I had mine; he just didn't have enough because no one could afford it," Wise says. Though most of his former clients now hire Wise, Porter still holds out hope that eventually they will return to him. "I don't want to step on his toes too much. I believe it's the best way to do business," he says. "He's using a lot of my old clients, but I think eventually they will want a higher level of service. I am hoping I can carve a niche." The recent Satmar campaign, the first religious campaign he has done since his competitor moved to town, came at a good time, and Porter was happy to make the extra cash. "The holidays are coming up so it works out well, because I will need to buy a lot of presents."