the underaged users are either discovered and kicked off or they move on to other shinier toys. In the limited amount of time I've been on this site I've seen some folks reprimanded and kicked off the site - just like some of the obnoxious members have lost the privledge to be here.

My suggestion is to require everybody to log in whether they're contributing to the forum or not. Lurking is fine but they should be required to log in.