In thinking upon your original question further Jay, the only remedy that comes to mind is to go ahead and open the uninteresting (to you) thread (either by first or last page) and then immediately close out of it by backspacing. Then the thread will drop from your current active list as it pretends that you've read it. I always use the "New Posts" tab for entering the forum. So the threads I've already read, with no new comments or activity, drop from the list. However if you are just going into the main forum without the "New Posts" feature it will of course continue to show all fairly recent threads regardless of whether you have already read them or not.