Israeli defense contractor Rafael Armament Development Authority calls it a "revolutionary concept in tactical intelligence," but really it's a wireless camera that's shot 500 feet in the air by a grenade launcher. And if a couple of hackers here at the hacking convention get their way, soon anyone will be able to buy this type of military grade technology for only US$500.

The Firefly can make the difference between life or death on the battlefield. Soldiers shoot it off and for eight glorious seconds it gives them a bird's eye view of the terrain around them, tipping them off to enemy positions. Then it crashes back to earth.

Private citizens can't buy these flying cameras, much less the 40mm grenade launchers used to shoot them. But Vlad Gostom and Joshua Marpet think they'd be great tools for a search and rescue operation, or maybe a boon to some local police force's SWAT (special weapons and tactics) team. So they're building their own version and showing off what they've learned at Defcon this week.

Their first test -- launched from a 37mm flare gun last week at a neighbor's farm -- wasn't exactly a raging success: The powder didn't fully ignite, the miniature camera flew about 30 feet into the air -- apparently too fast to transmit images back to the 5.8Ghz wireless receiver they were using -- and their parachute partially incinerated. But hey, it's a beta product, and this was their first launch, a learning experience. With a few more months of tinkering, the hackers hope to have a workable prototype that will rocket 250 feet in the air. "This was a good version one," Marpet said in an interview at Defcon.

They're not the only people who have military-styled do-it-yourself technology on display at Defcon. Using off-the-shelf components Mike Tassey and Rich Perkins converted a surplus U.S. Army drone into a flying that could be used to snoop on wireless networks or even mobile phone conversations.