The next heist/ransom movie isn't likely to be about jewels or someone descending upside down on a cable from the ceiling to avoid setting off alarms. And it's unlikely that anyone will be secretly rooting for the villains - certainly not anyone who uses a computer.

The newest ransom caper in real life involves hackers taking over an individual's or company's computer, scrambling or encrypting documents, videos, spreadsheets, databases, and other crucial files, and then demanding a ransom to unlock the files and make them usable again. Called "ransom-ware," this new malicious code combines the worst of spyware and Trojan horses.

It's the latest incarnation of hacker/ransom scams that started about five years ago with demands for payment to stop denial of service attacks or refrain from publishing sensitive information on the Internet. A more insidious form of extortion, also several years old and growing, involves putting malware on a computer through a virus, worm, or Trojan horse, pretending to "discover" it, and then directing the unsuspecting user to a web site that sells a product to get rid of it.

Encryption ransom-ware first surfaced in May, when hackers encrypted files, and demanded money to unlock them from a San Diego company called Websense that sells software that prevents employees from going to certain web sites - including those that might be security threats.

Websense learned of the extortion attempt from an individual whose files were garbled. The Trojan horse that encrypted his files included instructions to send an e-mail to an address for the directions on how to recover the files. It demanded that $200 in ransom money be deposited in an online account.

Rather than pay the ransom Websense mobilized its security team and discovered that the person working on the infected computer had visited a web site (since shut down) that exploited an Internet Explorer vulnerability to download a piece of malware. That malware, without the person's knowledge or action, then sent the computer to a second web site to download the encrypting code. That code searched all permanent and removable drives for 12 different kinds of files, including spreadsheets, garbled them, left the ransom note, and deleted itself.

Luckily, the encryption code was simple, and a security expert in Chicago who heard about the incident was able to write a decryptor and recover the files.

But that solution might not work the next time.

If using cryptography for extortion follows the same path as other cyber-crimes, the extortionists will develop increasingly sophisticated methods and won't be asking for a mere $200. Many in the IT and intelligence fields believe that terrorists and drug dealers are financing their activities through identity theft, stolen and sold credit cards and other cyber-crimes. If true, both the motive and resources can take cyber-extortion way beyond what we've seen so far.

The criminal foundation to spread extortion beyond the current level is already in place. Professional criminals can command legions of vulnerable computers to send denial of service attacks. Adding ransom-ware to their arsenal would pose a formidable threat that could have serious security and economic ramifications. The number of networks of rogue computers at the service of the criminal element rose to 30,000 networks from 2,000 in six months in 2004, according to a Symantec security official quoted in InformationWeek.

We're not anywhere near as prepared as we should be to deal with these threats.

A June U.S. Government Accountability Office study, based on input from security leaders at 24 federal agencies, said most agencies didn't even recognize the potential threats posed by spyware, phishing, and spam. "The blending of these threats creates additional risks that cannot be easily mitigated with currently available tools," the report said.

Confidence in local law enforcement and business' IT departments is also low. Nearly half of the 100 businesses that responded to a non-scientific online survey conducted by Carnegie Mellon University in 2004 said they wouldn't seek police help to investigate attempted cyber-extortion.

Asked why, most cited the downstream liability, followed by negative publicity, lack of confidence in the police, and fear of retribution. In addition, 45% said they didn't think their own IT departments were up to the task of preventing or dealing with a serious cyber-extortion attack.

Dealing with cyber-extortion is indeed a specialized field - and an expensive one. One online gambling site hired a vendor whose services ran about $100,000 a year to extricate it from a denial of services attack and prevent future attacks rather than pay the ransom.

The Carnegie Mellon study found that 17% of businesses had been the target of cyber-extortion, but that 68% of small and medium-sized businesses thought they were too small to be at risk and hadn't taken precautions or trained their employees.

Installing new security patches routinely and making sure all users have the latest signatures on their security software is part of the solution. Training employees to be vigilant is another.

The interconnectedness that the Internet brings to our businesses requires an updating of a 20th century admonition. When your computer talks to another computer, it may be talking to every computer that computer has ever talked to. Be safe.