Dear Andrew,

I also have a turing machine emulator.  I wonder if you would be willing to
put a pointer to it from your page?

It has been successfully built and run on VMS and UNIX.  It has a carefully 
designed user interface which uses a VMS-like 'help' facility and a 
command interface.  Both the 'help' facility and the command interface are
available as separate files in the distribution.

It doesn't use windows so that it will run on any character based terminal.

I have used it in my computer science courses to test and debug students
programs, and in that capacity I have found it to be very useful.  My students
have used it successfully as well in my formal languages class.

The URL is   http://mitlns.mit.edu/~dsw/turing/turing.html

It is also available by anonymous ftp at mitlns.mit.edu and at csvax1.ucc.ie
as well as other archival sites.

If you are interested, I'll clean up the page, and put in some more extensive 
documentation. 

                         Sincerely,

                          David S. Woodruff
                          MIT Lab for Nuclear Science
                          Boston University, Metropolitan College