Adeona works with Windows, Macintosh, and Linux. For Mac users, there is an add-on that periodically takes photographs using the laptop's built-in camera, to provide even more evidence to show the police. Kohno notes that the software is designed to improve the privacy of laptop-tracking systems. A savvy thief could still get around the systems by wiping clean a stolen laptop's hard drive before connecting it to the Internet.

Nonetheless, some other experts are impressed by the idea. "When your laptop is stolen, you want the chances of it being recovered to be as high as possible," says Lawrence Teo, vice president of development at Calyptix Security, based in Charlotte, NC, who has been testing Adeona on his own system for several months. A lazy or careless thief may leave the tool in place, Teo says, giving the software enough time to work.

"It's much easier to build a laptop-recovery system that is detrimental to privacy rather than one that preserves it," says Aviel Rubin, a security and privacy researcher and professor of computer science at Johns Hopkins University. "Most people are focusing on convenience and data-mining capabilities and forgetting about privacy. Seeing an effort to build something that will not compromise privacy even though it has every potential to--for me, it's refreshing."

Furthermore, since the source code for Adeona has also been published openly, Rubin says that users should feel better able to trust its security. "People can look at the software and see that there are no back doors, and that it really does preserve privacy the way that they say," he points out. "They're basically putting all their cards on the table."

The researchers are currently working on a version of Adeona for the iPhone, and Kohno hopes that other software developers will contribute to the project. "We're hoping other people will take this idea and extend it in other ways to make it more useful--for other types of electronic devices, or for other types of forensic confirmation," he says.