I upgraded to Inkscape 0.48 and so far it's not going too well, it crashes a lot but this time it usually saves your work correctly before dying. There are a few good things, though. One of them is the Spray Tool.
As I'm trying different drawing styles, one thing that is very nice and quite easy to do by hand (albeit a bit tedious) is 'crosshatching' to display shades. That is, using lots and lots of lines to represent shades, forming a pattern. My first surprise was that there is no standard crosshatch pattern for filling, which seems odd (it has stripes, sand and other strange ones). There must be a reason but in any case that type of crosshatching is always perfect and that is not what I wanted.
First I created a few lines, with the calligraphy tool set to Dip pen, width 1, Stroke size 0.1, in a 300% zoom. These numbers will vary wildly depending of what you do. I created a pattern like this:
Then I selected it, pressed the Spray Tool (new to Inkscape 0.48) and just sprayed with it to do the shading:
You can also enable pressure use for the spray tool, play with the width and in seconds do shading. I didn't put any effort on the actual drawing here, it's just an example :).
If you put a little more effort on the actual pattern to be used by the Spray Tool and apply it more carefully than I did I'm pretty sure the results will be quite good. I'll be trying it out soon!