mdk 1.2.3-1.1 (amd64 binary) in ubuntu hardy

 MDK stands for MIX Development Kit, and provides tools for developing
 and executing, in a MIX virtual machine, MIXAL programs.
 .
 The MIX is Donald Knuth's mythical computer, described in the first
 volume of The Art of Computer Programming, which is programmed using
 MIXAL, the MIX assembly language.
 .
 MDK includes a MIXAL assembler (mixasm) and a MIX virtual machine
 (mixvm) with a command line interface. In addition, a GTK+ GUI to
 mixvm, called gmixvm, and a Guile interpreter with an embedded MIX
 virtual machine called mixguile, are provided.
 .
 Using these interfaces, you can debug your MIXAL programs at source
 code level, and read/modify the contents of all the components of the
 MIX computer (including block devices, which are simulated using the
 file system).
 .
 Homepage: http://www.gnu.org/software/mdk/mdk.html