320 palate to 640 palate?

[steakman@wwa.com (SteakMan)]

        I know there is an INIT to change the desktop palate to greyscale 
but it is the funky 640 palate.  Does anyone know of a utility that will 
re-map the gradient greyscale of the 320 palate to the jumbled greyscale of 
the 640 palate?  Or, for that matter, has anyone seen a utility that change 
the 640 palate to an "approximation" of the colors used in a 320 picture?

Thanx :)

SteakMan