All Three Floyds beers (Three Floyds Brewing Company, Munster, Indiana) are fermented using a traditional Yorkshire Square system. It is a two-tiered fermentation vessel that allows yeast to collect on an upper deck, while the main fermentation commences below. Yorkshire Square systems are difficult to clean and maintain, and are therefore only used by a very small number of traditional breweries, but they produce a distinctive-tasting beer that cannot be replicated by any other method.
-From 365 Bottles of Beer for the Year
More info on Yorkshire Square fermenting can be found here
