hey I was wondering if there is a product to teach you how produce like 20 spongeballs in your hand or maybe after doing the sponge ball routine (classic one) instead of four balls in there hand one very large one.
Check out Eugene Burger's version. The multiple ball climax is taught on the first Volume of "Magical Voyages" and also in his book "Mastering the art of Magic".
They do make a growing sponge ball effect as well. A small ball puched into your fist becomes a much lager one. There is also a great sponge balls from hair effect done by Jeb Sherrill taught in his lecture notes. His website is www.sablemagic.com
I know on Ellusionist, Inside Magic teaches a sponge ball routine. However maybe your better off getting a DVD that is strictly for sponge ball routines.