You must be very familar with forums because there're so many on the internet about different topics. But do you ever thing of starting your own forum and run it on your own?
Before you launch a forum, you need to choose a forum script, it is better to start with a free forum script. Make sure that it is able to move information to another forum script should you want to change later. A good free script that does allow you to transfer your information is Phpbb forums. This is the script that many web hosts offer as part of their packages as well. When you want to change to a paid forum script, Vbulletin forums are also good and it comes with a migration tool for phpBB, which will allow you to easily transfer all your forum information without losing anything.
If you don't know how to do it, you could ask for help for free from this forum: www.theforumsforum.com.