you should have a look at http://www.phpbb.com. This is an open source forum software that could give you a lot of ideas for your forum here.
- Private messages
- See who is online
- Visual notification about changed topics since last visit
- View topics of a special user only
- View unanswered topics
- Jump to the beginning of an thread or to the end (last topic)
- See how many people viewed a thread
If you want to create a real community you have to be a lot more user friendly.