Just an idea floating through my head (its good to let them out before they do too much damage in there) ...
It seems lots of research continues to goes into improving layouting algorithms. I think Roassal could provide a good basis to visualize the operation of a layout algorithm as an animation. This could be useful to researchers as well as teaching demonstrations to students. The benefit for Roassal of being 'the platform' for researchers to develop and test their layout algorithms, would be ending up with all the latest and greatest of these built-in.
Perhaps a student project... One alternative could be a framework that manually inserted #signalUpdate's at significant points of the algorithm. Another could being extending the Smalltalk debugger to automatically send #signalUpdate's with each step.
cheers -ben