Altiris Inc.acquired the company in 2004. Blaser retired for the second time shortly thereafter. In March, Altiris released SVS as a free download on its Web site. Thousands of users downloaded the software in the first three months, Cook says. For corporate users, SVS is priced at about US$27 per node, compared with $100 to $125 per node for competing products.

In the first half of 2007, Altiris plans to add the ability to virtualize operating system patches. "If you find that the patch does cause a problem, it's just a matter of turning it off -- you haven't made any changes to your baseline machines," explains Rich Bentley,Altiris'market segment manager.

In 2007, developers also plan to combine SVS with another product, called Protect, which virtualizes an entire user session. When the user logs off, anything that was added or deleted can be wiped away or restored the next time the user logs in.