This was a cool thread to read through!! I have friend who is a machinist that makes these saws: Walk-behind and Hand-held Concrete Saws Manufactured by CS Unitec

Not sure where they are getting the blades from, I wonder if they can make a chop saw or table saw version of this?

I did see a new chop saw that slices thru 4" heavy angle like butter with no heat, special blades. Wonder how they would do with rock?