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.
Presently, VirtualBox runs on Windows, Linux and Macintosh hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista), DOS/Windows 3.x, Linux (2.4 and 2.6), and OpenBSD.
VMware Converter can be run on a wide variety of hardware and supports most commonly used versions of the Microsoft Windows operating systems. With this robust, enterprise class migration tool you can
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.