I've found YABB to be a great message/bulletin board
I've also tried discus (www.discusware.com
), but found YABB was better for my needs. It allows secure areas which the freeware version of Discus doesn't.
I've tried a number of chat board scripts as I'm not all that interested in remote hosted chat boards, but haven't found anything too amazing. Go to www.scriptsearch.com,
they have links to a number of different chat scripts.