This is interesting; reminds me of lisp in Haskell <a href="http://www.defmacro.org/ramblings/lisp-in-haskell.html" rel="nofollow">http://www.defmacro.org/ramblings/lisp-in-haskell.html</a><p>Is there any practical use for these kind of projects? I imagine it might make make it easier to write multithreading programs when the lisp is implemented in a purely functional language. At least Haskell seems to have decent multithreading support, I don't know about F#. Are there any other reasons other than curiosity to do this?