There are things you can do inside Poser's Sketch Room, but you have to work with the settings to get there. This was based on a couple of passes of some custom settings I worked up, merged together in Photoshop, to create a pencil look. But I imagine that had I worked a bit more with the black point setting, it would create a pretty gosh darn good pen and ink look as well.

docandraider.com -- the collected cartoons of Doc and Raider