I've thought in many forums, a huge improvement might be a system like this: 1) When new thread is started, it first asks about the topic, and won't let to write anything to the body of the message. 2) After author has written the topic, and press the "Make new thread on this topic"-button, the system will execute a search using those words on the topic and will show them in some relevance order to author. 3) Author then can choose either entering to some already existing talk-thread, or push "Yes, I really need to make a new thread"-button. Also unmercifully moderators would delete threads which has misleading or "bad" topic.