One of the original Lambda the Ultimate papers was "Lambda: the Ultimate Opcode" that described the hardware design of a computer whose ISA was Lisp itself. The paper is full of strange alien ideas like not having an ALU (Lisp is naturally symbolic; why would we need it?).

Guy Steele and Gerry Sussman also made a working processor from this design, but only fabricated a few prototypes (apparently it was absurdly slow, even by their standards). If you come by Gerry's office he'll gladly show one off to you.

http://repository.readscheme.org/ftp/papers/ai-lab-pubs/AIM-...