The adult entertainment industry may be the biggest business you've never thought of as a big business.
All connotations aside, by every account the porn business is just as big as—or bigger than—plenty of other mainstream media.
(Read more: Adult Entertainment Expo 2014)
While many will quibble over what should or should not be counted in the total figures for various media industries, at $12 billion a year porn definitely earns a place in any list of significant American industries.
