Since starting to work recently with ECJ, I've posted several messages about 
my experiences on my blog, Invisibe Hand. It is available at 
dvunkannon.blogspot.com.

My most recent post shows how I've built on the charting support in ECJ to 
create charts with multiple data sets per chart that report different 
statistics about a subpopulation.

Please visit and leave some comments!

Sean - since the work I am blogging about combines several incremental 
changes to ECJ in the areas of a new BitVector problem, reading custom 
parameters, and collecting and charting custom statistics, I was wondering 
if you would like me to write it up in the form of a tutorial? It's about 
the same difficulty as Tutorial 2, just in a slightly different direction.

Cheers,
David vun Kannon