how you can convert a physical Windows system (XP, 2003, 2000, NT4 SP4+) into a VMware virtual machine with the free VMware Converter Starter. The resulting virtual machine can be run in the free VMware Player and VMware Server, and also in VMware Worksta
With Microsoft® Virtual PC 2007, you can create and run one or more virtual machines, each with its own operating system, on a single computer. This provides you with the flexibility to use different operating systems on one physical computer.
innotek VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.