PS - That's not Daenerys!
I wonder how many other people have noticed that? ;-)
I've done a little bit of research on the various board/firmware options and here is a summary I will put here so I can refer to it in the future.
There is a firmware called "Smoothieware" that is basically GRBL for 32-bit ARM.
("The motion control part is a port of the awesome grbl." -- from github)
But it has more features, and can be used for CNC machines, 3D printers and laser cutters.
The Smoothieware firmware has a board that goes along with it, the Smoothieboard.
The "Cohesion 3D" board is from another guy, Ray, who developed a compatible board.
The Cohesion 3D board can run stock Smoothieware, a smart design decision.
There is a version of that board that is designed to be a drop-in replacement for the Chinese K40 laser.
There are other Smoothieware compatible boards:
Azteeg X5 mini WIFI 32BIT All-in-one Controller, maybe more...
Checking Aliexpress, I see the Chinese have been busy working a whole bunch of compatible boards:
Looks like you can get one with a sexy touchscreen for $75!
The cheapest is $40.
Apparently the Smoothies have a problem with the clones
("If you are using a MKS or an AZSMZ board, please note that those boards are toxic to the community and project.")
Toxic boards? It seems some of the clone boards CAN'T run stock Smoothieware, a dumb design decision.
Cohesion 3d G+