I'm experimenting with using Fractal_Sum in Displacement to create a brush cut type hair. Which works okay, except I haven't figured out how to get specular. I guess it doesn't work on node-based displacement? or is there a workaround? I've tried various ways of connecting a Specular to the Fractal_Sum (from the Alternate_Diffuse channel), but no luck....

Without shader it's difficult to help you ;)

Well, maybe you can't help, anyway, since you don't say whether it's possible to generate specular on node-based displacement. If it's possible, then my non-working shader is the wrong thing to post. :)

I do not beleive this is possible.  the specular seems to only apply to the original surface sub-poly and not the sides of the displaced sub-poly.