A couple photography ones:

http://www.dpreview.com/forums/default.asp

http://www.photoworkshop.com/phpBB2/index.php

and a Photoshop one:

http://www.adobeforums.com/cgi-bin/webx?14@@.2ccd8a3f

I mostly read, but have posted some. When I post it's always a ?.
Katz