So we're studying heap dumps for our Java app to try to determine why our models are taking up as much space as they are. After staring down some of the models, I dropped in a bit of new code.
The model that I was working with -- one of the smaller ones, admittedly! -- shrank by almost 10% in its memory footprint. Larger models probably won't shrink quite as much, but it was a gratifying result.
Now to see if I can use this trick in some other places. :)