The ascent of the Internet as the supermarket of choice for deviants has spurred law enforcement authorities to step up their trolling of the darkest corners of the Web in an effort to lure sex offenders to their arrests.
Examples abound, some of outwardly decent people, indeed pillars of the community, who have sought to have sex with children through sites such as Facebook and MySpace.
Most worrying to law enforcement, however, is a small but apparently growing subset of these predators who are hooking up online with parents or guardians willing to prostitute their children, sometimes as young as infants.
These are the most dangerous predators going after the most vulnerable victims, and finding and prosecuting such cases provide the opportunity to take both the criminal parent and perpetrator off the streets, according to criminal justice experts who spoke to ABC News.
"We're posing as parents more than we have in the past," said Arnold Bell, chief of the FBI's Internet sex-crimes unit, Innocent Images. "The landscape changes all the time and we have to modify our behavior as predators modify theirs. When we go on posing as parents with kids for sale, we're contacted very quickly by pedophiles."
The vast majority of inappropriate sexual contact online involves adult men and children age 11-13, kids old enough to operate a computer and leave their homes on their own, but young enough to be manipulated by a grown-up, he said.
Pedophiles, however, are by definition attracted only to prepubescent children and by necessity often have to ingratiate themselves with children's parents to gain access to their victims, Bell said.
"Sometimes pedophiles feel the parents are consenting on behalf of their kids," Bell said. "They think it's OK because the parents are allowing it. It allows them to justify what they're doing in their own heads, but it's completely invalid in court. It's completely invalid in any sense."
Twice in recent weeks, police sting operations in which law enforcement officials portrayed themselves as parents looking to prostitute their children yielded arrests.
On Friday J.D. Roy Atchinson, an assistant U.S. attorney, who police say chatted with an undercover detective who he thought was the father of a 5-year-old girl, killed himself in the Michigan federal prison in which he was being held.
When police apprehended Atchison, 54, on Sept.16 at the Detroit airport, he was carrying a teddy bear and jar of pertroleum jelly.
On Sept. 29, in a separate case, Daniel Barron, 56, a producer at CBS Sports, was also arrested. Authorities say they posed as a father willing to let Barron have sex with his 11-year-old daughter in exchange for Miami Dolphins tickets. Barron has yet to enter a plea, according to court documents.
That both men were respected members of their communities and not "guys in trench coats," the FBI's Bell says, should indicate to parents that sex offenders can come from all walks of life.
"The Internet gives them the ability to communicate in a way they never could before. There is a sense of anonymity and security and a feeling — despite all the news — that no one is watching," he said.