In May, the U.S. Department of Veterans Affairs learned the hard way that laptop computers are easy targets for theft: burglars struck the home of a department analyst who'd taken his laptop home without authorization, and made off with social-security numbers, birth dates, and other personal information for more than 26 million veterans and spouses, as well as 2 million active military, National Guard, and Reserves personnel.

Stolen laptops equipped with Absolute Software's Computrace software, also called "Lojack for Laptops," report their Internet addresses to a central server, which can lead police to a street address. (Courtesy of Absolute Software.)

That well-publicized incident -- the latest in a string of thefts compromising key data from large organizations -- is reawakening interest in technologies for protecting laptops and prompting security companies to tout their latest advances.

These new systems, which aren't intended to prevent theft, but rather mitigate their consequences, come in three flavors: tracking software, encryption, and "kill" switches that can make a laptop's data self-destruct.

Extra layers of protection are needed because the password and encryption mechanisms that come with most laptops are weak or inconvenient, says Jack Gold, head of J. Gold Associates, a market research firm in Northborough, MA. "There are hacker tools that let you get around [passwords] very quickly, or you can boot from a CD," Gold says. It's true that any laptop running Windows XP Professional has an optional encryption function that should defeat thieves, but using it slows down normal file access.

One solution, then, is a tracking system, such as Computrace, run by Absolute Software of Vancouver, Canada. William Penn University in Oskaloosa, IA, turned to the system this year, after about 500 laptops in one of its colleges went missing, says Curt Gomes, the university's IT supervisor. The university decided it had become uneconomical to try to hunt down each machine manually. Instead, Gomes decided to try laptop tracking -- a technique that's been around for a decade, but recently has seen sales growth of 50 percent per year.

Each machine subscribed to the Computrace service typically reports to a company server once a day via the Internet. If the computer is reported stolen, the server will instruct it to start sending messages every 15 minutes. And if the missing machine's Internet address can be pinned down to a street address, police will soon show up there, according to company spokesman Les Jickling. In fact, a week after William Penn signed up for the Computrace tracking system, a laptop stolen out of a car was recovered by police five days later.