http://toolserver.org/~erwin85/randomarticle.php?lang=en&family=wikipedia&categories=Good+articles http://toolserver.org/~erwin85/randomarticle.php?lang=en&#38.

http://toolserver.org/~erwin85/randomarticle.php?lang=en&family=wikipedia&categories=Good+articles http://toolserver.org/~erwin85/randomarticle.php?lang=en&#38... selects randomly from their list of Good articles, which is the nearest thing I'm aware of, though still not quite what you're describing.