here's a little trick to give your 2d scans a little shade just in seconds. all you need is photoshop...
open a file
select all (crtl a)
copy (crtl c)
paste (crtl v)
change layer style from normal to overlay
decrease layer opacity to 60 %
filters/other/minimum (values between 4 and 8)
filters/blur/gausian (values between 4 and 10)
filters/noise/add noise (10 - 15 %, uniform, monochromatic)
select 'move tool'
use 'arrow keys' to move layer 2 units down and to the left
if you use photoshop6 you can record these actions!!!