From the Creator:
QEMU is a FAST! processor emulator. By using dynamic translation it achieves a reasonnable speed while being easy to port on new host CPUs. 

see: http://fabrice.bellard.free.fr/qemu


Packager Notes:
This is basically another form of Bochs. See my notes there.

It may be fast, but I have been unable to get Windows 98 to boot from it due to
the lack of certain error checking.  Bochs gets the same errors but allows one
to bypass them and boot into the OS. I have yet to try it with Windows 95, but
this is my next project.

You need a configured virtual harddrive and an OS loaded onto that drive to use
QEMU. Drives configured for use under Bochs or other virtual OS loaders seem
to work.