I attended a cask ale seminar in the mid 90s where that 'other beer guy', Roger Protz, gave a talk on cask ale. He began, "Cask ale is not a matter of life and death. It's of much more significance!"
From The OED: "Cask ale is beer brewed from traditional ingredients, matured by secondary fermentation in the container from which it is dispensed, and served without the use of extraneous carbon dioxide."
More on cask ale
[ update: 2007 Protz lecture ]