Also worth a read: <a href="http://www.cs.umbc.edu/331/resources/papers/Evolution-of-Lisp.pdf" rel="nofollow">http://www.cs.umbc.edu/331/resources/papers/Evolution-of-Lis...</a>
That's one of the reasons why I want to learn VHDL or something in this lines: I would love to resurrect some of these machines, even if in emulated form. Has anyone here ever tried this?