Here's an interesting forum app in that it's probably unlike any other you've seen, yet will be instantly useable for anyone familiar with Outlook Express:
Seems like a rather small feature list compared to some forum apps, but hey, small and sweet.
Multiple forums supported
Threaded conversations
Rich text messages
Admin gui for adding/removing forums and editing/deleting messages
Instantly usable for anyone who's used Outlook Express
http://www.phpguru.org/static/PariahBB.html
