"How would you like to run several operating systems at once on the same physical hardware with virtually no performance overhead -- and for free? That's the promise and the purpose of Xen, a relatively new open source project that turns one piece of hardware into many, virtually. If you're looking to cut costs or maximize usage or both, follow the path to Xen.
"Hardware virtualization allows multiple operating systems to run simultaneously on the same hardware. With such a system, many servers can run on the same physical host, providing more cost-effective use of valuables resources, including CPU, power, and space..."
