I just put up a review of the Pascaline Danis Final Load Balls from Jeremy.
http://www.cupsandballsmagic.com/Pascaline-Danis-Load-Balls.html It's interesting to note that they are painted underneath to help blend in with the crochet. I've not seen this before but it seems like a good common sense idea...
Anyhow... I thought a poll on favourite ball core material might be in order. I will state for the record that I prefer wood, it can be washed, I like the weight (for wand spin and they don't bounce) and for final loads they can be "smacked" together to showthey are not sponge.