Heh, maybe you'll get a kick out of http://nand2tetris.org/ (if you haven't come across it already). I finally finished part 1 of the course (implementing the Hack machine) and it was one of the best and most challenging learning experiences I've ever had. My plan is to do part 2 (VM, high level language, OS) with Lisp instead of the language they implement. That's been the plan for the last 6 months, anyway...
Cool, I'll check it out. I have a few lisp projects in the works. I started making a simple lisp operating system for 16-bit intel by forking MikeOS, which is an awesome project (didn't get that far). Then I developed a Forth VM / Compiler to build a lisp on top of (since compiling to my own forth assembly will be easier than targeting a real assembly). I got the forth compiler and vm, no lisp yet =T
