I really love hatching and cross-hatching. If it didn't take so long to do this stuff I would totally skip computer aided toning but alas.
You can see me doing some nifty cross-hatching in the third panel of this page. You draw about three to seven lines a set and then the paper is turned about 30 degrees and I add another set of marks in a row. Turn, turn, turn and you get these cool spiraling patterns in the cross-hatching. Ergh, it's hard to explain in words but yeah I really love this stuff.
Sadly, I'm not even sure if I'm doing this correctly as some of the printed versions of this kind of cross-hatching that I was referencing is printed in these really small manga, the series is called 'Swan.' Which is this old school Shoujo manga I found. Although I've seen the technique used elsewhere the 'Swan' cross-hatching is particularly over the top and cool. Their tree bark cross-hatching is awesome.
It's too bad there is such an emphasize on speed for comics. So, I don???t think I'll ever really mastering this technique fast enough to be really useful. However I'm defiantly using it for single pictures. Since it's a lot of fun even if it is mindless work. I like to fling the comic page around in a dangerous way. =D