WYSIWYG NPR: Drawing Strokes Directly on 3D Models

Found this one during surfing the internet.

The paper and demo is @ http://www.cs.princeton.edu/gfx/proj/wnpr/
The software is @ http://jot.cs.princeton.edu/. A python script is included to export Blender mesh.

another totally off-topic one: Suggestive Contours
GPL-ed source and binary files for linux and windows are both downloadable at http://www.cs.princeton.edu/gfx/proj/sugcon/. PLY, OFF, 3DS, and Wavefront OBJ files are supported.

This may be turned into a Blender Pencil Render Engine, I think so at least.

Sounds very interesting!