I'm starting to worry about the Internet. Yes, perhaps I should have worried before now--call me blind. I feel nervous going anywhere on the Web except large, well-known sites such as Google, Amazon, or Microsoft--unless I'm running at least three real-time spyware blockers.

That might be a bit of an exaggeration. I know enough not to fall prey to browser helpers, and when I visit a site that wants me to load an ActiveX control "to maximize my ability to enjoy the site," I beat feet away from the site quickly. I disable visual styles so that I can't be gulled into clicking what seems like a "close" box but is actually a "Yes, download that file to me" button. I use the Microsoft Internet Explorer (IE) Add-on Manager feature in Windows XP Service Pack 2 (SP2) to take a quick peek at what's loaded in my browser, and I run Sysinternals' Autoruns tool to ensure that nothing untoward is being loaded automatically. But, then, I'm a geek. So I often wonder, how most people deal with spyware. After recently helping about a half-dozen friends figure out why their systems run so slowly all of a sudden, I have the answer: They don't. Most people have more spyware installed on their computers than a poorly maintained boat hull has barnacles. What's the solution?

The answer is simple: virtual machines (VMs). When I want to visit an unfamiliar Web site--one that I suspect might try to fool me into installing some type of spyware--I just fire up VMware's VMware Workstation desktop virtualization software and run a copy of XP SP2. I use VMware's snapshot feature to back up the VM's state before browsing. I use the browser in the virtual copy of XP to read Web content or to download a file. After I download a file, I can drag that file from the VM to my actual desktop and run it through the machine's antivirus and antispyware software. Then I click the Revert button that restores the VM to the state at which I started. Consequently, I can feel fairly certain that anything that snuck by me and was installed on the virtual XP system is now gone.

Unfortunately, VM technology requires some investment--about $200 for a VMware license (some of the best money I've ever spent) and an XP license--and so might not be a reasonable solution for some users. But consider this: Microsoft is concerned about spyware and has invested quite a bit of money in procuring, then enhancing antispyware technology. The company could, if it wanted, implement a solution like mine with technology it has on the shelf.

What if XP came with a reduced version of Microsoft Virtual PC, the company's VM technology? That cut-down Virtual PC would be able to run just one VM, a prebuilt XP SP2 image. You could then use the virtual XP system to browse the Internet, open email attachments, and so on. The VM window would have a button that says, "I'm done for the day." Press that button, and the VM reverts to the original image, in seconds. Microsoft already offers a free antispyware tool and will soon offer a free antivirus tool; the company could modify the code that lets you drag files from the VM to the real XP desktop so that each file is automatically checked for viruses and spyware. Call the tool "XP Buddy," or perhaps "Surfer Shield." If Microsoft sufficiently restricts this XP Buddy version of Virtual PC, it shouldn't eat into sales of the regular Virtual PC version, and the company could sell XP Buddy for $30 or so.

One of my favorite parts of computing has always been the Undo button; XP Buddy simply extends that feature. Or, to misquote a tag line from an old '70s movie, "Virtual machines mean never having to say, 'how'd they get my credit card?'"