Putting a hard dollar value on the adult world as a whole has never been easy. That's something that has only grown more challenging in the past decade. Traditional film studios and publishers (like Playboy, Penthouse and Vivid Entertainment), which used to be the industry's biggest names, are shadows of their former selves, in large part due to the proliferation of cam sites and streaming hubs. That said, there are some estimates – and some companies have disclosed firm(ish) numbers to underscore the size of the industry.