An open-source Web-based operating system called eyeOS is getting a big boost from IBM. The computer giant has begun selling high-end mainframe servers with eyeOS pre-installed, hoping the operating system will entice customers who are hesitant about using cloud computing.

Managed by a small company based in Barcelona, eyeOS lets users access a virtual desktop through a Web browser. The user can treat that virtual desktop like the desktop of a regular PC, launching and running applications within it.

Though individuals can use the operating system over the Internet through a site hosted by eyeOS, IBM makes it possible for customers to host the service themselves. With the software installed on the mainframe server, a company could offer virtual desktops to its employees, who could then access their “work computers” from any device.

Unlike projects like Google’s ChromeOS, which is designed to let people access the entire world of Web applications through the browser, eyeOS is designed to access a specific set of applications “installed” on the virtual desktop. Using the system, an organization could provide employees with productivity applications, its own custom applications, and access to proprietary data. The ability to access these through a single Web-based operating system, says the project’s founder, Pau Garcia-Mila, saves users from needing passwords to different Web-based services. It also allows the applications to be more compatible with each other.

Cloud computing most often means running data and applications on remote servers hosted by a company such as Amazon.com. New technologies allow the hosting company to share its processing and storage resources efficiently among all its customers, enabling it to offer low prices. Customers of cloud providers save money because the rates are low, they don’t have to buy their own equipment, and they can buy just as much computing power as they need, changing the quantity as their demands fluctuate.

IBM’s goal with this product is to help customers build “private clouds,” since some companies hesitate to host data and applications on public clouds, often due to concerns about security and reliability. The idea of a private cloud is to set up–on a company’s own servers–the same sorts of efficiencies used by cloud providers, without having to entrust sensitive data to an outside organization.

“For most well-established, large enterprises, there is in general some distrust with public cloud services,” says IBM’s mainframe cloud initiative leader, Andrea Greggo. “This is driving the focus on wanting to contain these environments behind [a] firewall but still benefit from the value of cloud.”

Customers can use IBM’s new servers for the data processing typically expected of mainframes, but Greggo says the servers also let customers take advantage of products such as eyeOS.

But Frank Gillett, a principal analyst at Forrester Research, calls the term “private cloud” an oxymoron. He compares what IBM offers to virtualization services already offered by companies such as VMWare.

Gillett acknowledges that eyeOS is different from other virtual desktop systems because it allows users to access the desktop through a Web browser instead of a special application. Nonetheless, he remains skeptical because eyeOS is not based on a popular operating system such as Microsoft Windows. He believes many businesses will stick with virtualization services that let them use familiar software. Though some companies have tried to build Web-based operating systems, he says, “None of these startups have made it into the mainstream conversations.”