That’s a Lisp Machine in Your Pocket
hackaday.comZ80 is not a Lisp Machine.
But the 1M memory is not in the address space and maybe there is some external CAR/CDR-processing, so the Lisp-part is actually executed elsewhere.
It is quite sad however that the Z-generation had to waste their time redoing old stuff instead of inventing something totally new: http://timonoko.github.io/jemma/smuisti.html
This is an eZ80: a 24 bit processor backwards compatible with the Z80, which can address 16 megabytes of external memory. It's called "8 bit" due to the data bus width, but the programming model is 24 bits. It has 24 bit registers and can load, store and operate on 24 bit quantities. It runs at 50 Mhz and is pipelined, so that in Z80 mode, it runs 3X faster than the original Z80 at the same clock rate.
I think that a decent Lisp implementation is possible on this machine, with useful embedded applications.