Microsoft Windows Virtual PC (Windows XP Mode, Virtual PC 2007, Connectix Virtual PC) : Use different operating systems on one physical computer
Windows Virtual PC (formerly Microsoft Virtual PC and Connectix Virtual PC) is a virtualization program for Microsoft Windows. In July 2006, Microsoft released the Windows-hosted version as a free product. In August 2006, Microsoft announced the Macintosh-hosted version would not be ported to Intel-based Macintosh computers, effectively discontinuing the product as PowerPC-based Macintosh computers are no longer manufactured. The newest release, Windows Virtual PC, is available for Windows 7 hosts.
DOSBox (DOS Emulator) : Emulate any game or application that used to run under MS-DOS
DOSBox is a DOS-emulator that uses the SDL-library which makes DOSBox very easy to port to different platforms. DOSBox has already been ported to many different platforms, such as Windows, BeOS, Linux, MacOS X…
