Nelson Chu has made the following announcement...
<blockquote>

I'm glad to let you know that our work on ink dispersion simulation is accepted by SIGGRAPH 2005. I've just made a webpage for this work :
http://visgraph.cs.ust.hk/MoXi/

BTW, Our prototype is built with GLScene, of course!

</blockquote>

This movie, of the technique in action, has to be seen to be believed, it looks exactly like they are painting on real paper. Some really impressive work! I wonder if someone will turn this into a rendering technique for some games.