Brief is a Forth-like concatenative language with quotations inspired by Factor and Joy. Very simple. It has taken on many forms over the years: an embedded VM for microcontroller programming with .NET IL translation, an AST form used for program synthesis for learning robotics tasks, a JavaScript-based version for web programming, and several others.
Most variations (not included here) were developed at Microsoft and remain internal.
Currently (JAN 2021), I'm working on yet another variant here.