MobaLiveCD - Portable Live CD Emulator

mobalivecdMobaLiveCD is a Free Portable Live CD Emulator that utilizes a Software front end for Qemu to enable you to (Run Linux on Windows). Run your Linux Live CDs and other ISO files portably from within Windows without rebooting.

DOSBox - Portable DOS Emulator

dosbox-screenshotDOSBox is a portable DOS emulator or Portable DOSBox that can be used to run many old DOS games or applications that cannot be run on a modern Windows Operating System. It is great to use for those old DOS software applications or games you may have sitting around collecting dust.

Jnes - Portable NES Emulator

jnes-screenshot-featuring-metroidJnes is an old school (NES) Nintendo Entertainment System Emulator that can be run from a portable device such as a USB flash drive. Jnes also includes an advanced database of "Pro Action Replay" and "Game Genie" cheat codes.

Mac On a Stick - Portable Macintosh on a USB stick

mac-on-a-stick-screenshotMac On a Stick aka: Mini vMac, just as the name imposes, is a portable Macintosh emulated operating system that can be booted and run from a USB flash drive. Although for most, it isn't a complete replacement operating system, a MOS installation can include many useful applications running from an emulated Mini vMac (a Macintosh Plus emulator).