Script-Fu -> BW from Graphic
by Paul Sherman
A derivative of BW Film Simulation, made for use specifically for rendering clip art in greyscale. High-Contrast setting will yield a "sketchy" look instead of the "blockinesss" usually rendered from graphics when converting to grey.
BW from Graphic Dialog

Original Image

Greyscaled image:
(script NOT used)
Script Results:
Run with all parameters at their default settings.