Personally, I am not a fan of these lookma-my-interpreter-in-zero-lines stuff. Take a look at http://norvig.com/lispy.html. Bigger, but well engineered.
Yes, I'd prefer more exotic stuff like Scheme-to-C compiler written in Prolog or any other combination, not bounded by nbr of lines.
Thanks for the feedback guys! I intend to do more interpreter/compiler projects so perhaps you will end up considering one of my future projects sufficiently interesting or exotic :)