I don't quite know how you'd measure, such a thing, but this is still impressive enough to make me want to watch Big Wednesday, again.
http://www.surfertoday.com/surfing/6412-garrett-mcnamara-rides-the-biggest-wave-of-all-time-in-nazare
[video]http://www.surfertoday.com/videos/6411-the-30-metre-wave-by-garrett-mcnamara[/video]
http://www.surfertoday.com/surfing/6412-garrett-mcnamara-rides-the-biggest-wave-of-all-time-in-nazare
[video]http://www.surfertoday.com/videos/6411-the-30-metre-wave-by-garrett-mcnamara[/video]