America´s most prominent volcanoes-Mount St. Helens in Washington State and Kilauea in Hawaii-might, at first glance, seem similar: Both attract tourists, and both erupted in the past 25 years. But their destructive powers come from quite different volcanic origins.The erupting vents beneath Kilauea´s surface carve an elaborate lava-tube system into the Hawaiian countryside. The thin basalt lava from the volcano´s vents flows long distances under the cooled surface crust to produce the gradual slopes characteristic of shield volcanoes.

Humans are fleeting visitors on this roiling rock in the universe. On December 26, 2004, at 58 minutes and 49 seconds past midnight GMT, Mother Earth reacquainted us with this immutable fact. For millions of years, a creeping slab of Earth´s crust—the India Plate—had been grinding headlong into a similarly stubborn chunk of rock called the Burma Plate. Like a clash of Brobdingnagian armies, millennia of pent-up kinetic energy suddenly exploded from the seabed, a scant 100 miles from Sumatra, Indonesia.

Take a scenic flight over the summit of Mount Vesuvius in Italy, and the view below is chilling. A dense patchwork of urban sprawl from the nearby city of Naples laps at the flanks of one of the most violent volcanoes on Earth. Since A.D. 79, when Vesuvius exploded with little warning and entombed Pompeii and its 3,000 townsfolk under 15 feet of scalding ash, the volcano has erupted at least 30 times.

For years, the phrase â€PDAâ€phone combo†brought to mind clunky bricks that appealed to only the most connectivity-crazed early adopters. But the latest incarnations of these devices, now known by the more marketing-friendly tag â€smartphone,†are finally fit for the rest of us. So why do you want one?Beyond the obvious calling capabilities, smartphones keep your calendar and address book close at hand (and ever more easily synced with your PC), provide access to e-mail and the Web,

It takes Scott Kiser only a split second to name the one city in the U.S., and probably the world, that would sustain the most catastrophic damage from a category-5 hurricane. "New Orleans," says Kiser, a tropical-cyclone program manager for the National Weather Service. "Because the city is below sea level-with the Mississippi River on one side and Lake Pontchartrain on the other-it is a hydrologic nightmare." The worst problem, he explains, would be a storm surge, a phenomenon in which high winds stack up huge waves along a hurricane´s leading edge.

For years, the phrase â€PDAâ€phone combo†brought to mind clunky bricks that appealed to only the most connectivity-crazed early adopters. But the latest incarnations of these devices, now known by the more marketing-friendly tag â€smartphone,†are finally fit for the rest of us. So why do you want one?Beyond the obvious calling capabilities, smartphones keep your calendar and address book close at hand (and ever more easily synced with your PC), provide access to e-mail and the Web,

Agendus Professional Don´t confuse this powerful personal management tool with the anemic programs that come stock. Calendar, messaging, meeting planner and a rollover To-Do application are all bundled into one integrated product in which they share information and operate together seamlessly. It also integrates with desktop applications such as Outlook and Act.

The human thermal vacuum chamber at NASA's Johnson Space Center in Houstonthe only facility of its kind in the worldlooks like a prop from a Jules Verne movie. Picture a colossal metal drum surrounded by gargantuan pipes and fittings leaking fluid and spewing steam. By sucking air out of the chamber and running liquid nitrogen through the walls, engineers can lower the temperature to 140

It's July in Las Vegas, and the relentless midday desert sun has already pushed the outside temperature into three digits. But here inside the Alexis Park Resort, it's cool and dark. The bar is open, and the room is beginning to fill up. It's 1 p.m., the big game has just begun, and, as you'd expect in the world epicenter for sports gambling, the room glows with the light from dozens of screens catching every nuance of the action.But these aren't television screens, they're laptops. And the motley assortment of guys peering into them and busily clicking away at keyboards aren't gamblers looking to score some last-second intel on the game, they're hackersand this is the game.Welcome to Def Con, the self-proclaimed "largest underground hacking event in the world."

â€This must be the new trick this year; they said â€OK, don´t shave,´ †says Priest, a Def Con â€goon†(that is, a conference security guard and friend of organizer Jeff Moss). Priest is supposed to be introducing a panel presentation on wireless security, but instead he´s talking to an otherwise clean-cut attendee with a two-day beard and a nervous smile. Until a moment ago, the 40-something guy with the stubble had been sitting quietly in the audience. Then a kid in his row decided he looked suspicious.