Larger than a basketball...smaller than a medicine ball.
I just pulled it all apart and have about 10 significant pieces, and 1 that has too many heads to even attempt to count. That piece alone likely has 50-100 heads, depending on how large a head has to be before you count it.
Here's a photo of the colony...
__________________
400 gal reef. Established April, 2007. 3 Sequence Dart, RM12-4 skimmer, 2 x OM4Ways, Yellow Tang, Maroon Clown (pair), Blonde Naso Tang, Vlamingi Tang, Foxface Rabbit, Unicorn Tang, 2 Pakistani Butterflies and a few coral gobies
My Tank:
http://www.canreef.com/vbulletin/showthread.php?t=28436