Home / Sponsored StoriesSponsored by The University of Waikato Solving NZ's biggest problems19 Dec, 2008 11:00 AMSponsored by The University of Waikato Subscribe to listenAccess to Herald Premium articles require a Premium subscription. Subscribe now to listen.Subscribe nowAlready a subscriber? Sign in hereListening to articles is free for open-access content—explore other articles or learn more about text-to-speech.SaveShareShare this articleCopy LinkEmailFacebookTwitter/XLinkedInReddit