Great idea, but it'd be very difficult to do. It's basically why we have the useful posts, to keep a constant of the more important posts going around. The FAQ might be useful, but we already have constant posts containing links and other important information. I'd personally request to just add more 'useful posts', and/or a way to make them more visible. Perhaps next the tabs with all activity etc on them, we could have one called 'important', and have selected posts appear there instead.