So here's another language which doesn't look very Rebol-like but is by Refaktor who is Rebol-inspired:
Notably, it is written in Go. (I've mentioned that increasingly I have been leaning toward modeling things after Go for a runtime. It would of course be easier to do by actually writing the runtime in Go, vs. trying to reproduce the effect in low-level C code. )
It's probably very interesting, but I don't really feel like looking at it right at this moment. Maybe someone else can study it and explain what it's about in a reply here.
The main carry-away I'll take for the moment is the 1:1 language-designer:user ratio that Rebol users are inevitably converging toward.