August 03, 2007 - Trust nobody.

That's what organizers of the 15th annual DefCon hacking conference are telling attendees Friday, after being tipped off that the TV news program Dateline NBC has sent a producer with a hidden camera to investigate the show.

Cameras of any kind are a strict no-no at the show, which bills itself as a gathering for hackers, both legitimate, and not-so-legitimate, and takes special steps to ensure the privacy of its attendees. The show keeps no list of attendees, except for press and speakers, and there's only one way to get in the door: paying $100 cash.

DefCon organizer Dark Tangent (a.k.a Jeff Moss) said that he's concerned that the show's producers may sensationalize what they see and undermine the show's goal of fostering a free exchange of ideas. "We researched them online and we see [the show's producers] do hit-and-run pieces," he said. "It's not actually research and news. It's just sensationalistic nonsense. And that makes us nervous."

Moss says he's been told that Dateline Field Producer Michelle Madigan is at the show with a hidden camera. NBC did not immediately reply to a request for comment.

Media and bloggers have gone undercover at DefCon in the past, but nobody of the stature of NBC has ever tried this, Moss said.

"I'm concerned that some impressionable kid... is just going to get cornered and is going to start bragging about stuff," he said. "The next thing you know, he's on nightly news."

DefCon runs through Sunday at the Riviera Hotel and Casino in Las Vegas.