5. PHPBB (http://www.phpbb.com) - This has to be the most talked about free PHP based bulletin board system available. However, I found it to be very rough around the edges and missing some key features (i.e. secure email addresses) needed in today's environment. It also has the least appealing default style of all the systems listed here. PHPBB could be a winner with its opensource nature, however it still has a long way to go before being a leader. My Personal Rank is 2 out of 5 stars.
What is your view of phpBB?