There are cross hatch tiling textures in the Mapping Elements section. RobA made one which looks like the one madcow is using.
a link would be appreciated. I'm not finding it.
Here's a link to a tutorial by Dyson Logos on how he does his crosshatching by hand:
And here's another:
Here's the texture. Enjoy!
Yay, useful links! Now I can read up on how to do it right. The problem with using other peoples crosshatching is it may not fit the line size or detail of your own maps, as well as the satisfaction of using your own elements. Wonderful to have tutorials on how to do it yourself.