Tutorial (link): Sketch Effect, Anisotropic and History Brush

[DannyRaphael]

===> See palms' description of the method below. The link to the original site no longer works.

[palms]

Pity this link isnt working anymore as it is one of my favorites
but this is the gist of it

dup original >desaturate >duplicate
invert top layer
change top layer to colour dodge
gaussian blur ( so can see soft detail)
diffuse ( aniso )
new layer
use history brush to bring back some soft colour using a chalk brush ( or similar )
change blend mode to hard light


works nicely on furry animals ( not tried on buildings etc )
this was done quickly just to give a rough idea
photograph from www.geekphilosopher.com

Palms