For those who run multiple operating systems, Microsoft has released its latest version of Virtual PC, which allows users to quickly switch from one OS to another by simply clicking the mouse. Although Microsoft once charged for this software, it is now free to everyone, although it doesn’t work on home versions of Windows (ie. not XP Home or Vista Home Basic/Premium). It is capable of running a number of different operating systems, although some Linux distributions can be complicated to setup. It works with both 32-bit and 64-bit operating systems and can be downloaded
here.
Source: DailyTech