The lesson here is that stupid ideas you would not normally consider can work if they hit the right demographic.
Another example, I Can Has Cheezburger.
It's either brilliantly stupid, or stupidly brilliant. Whatever. It hit a trend exactly in the sweet spot, and went from zero to a 500,000 page views a day in six months.
The trick is in being able to imagine markets that others aren't serving, Of course, then you've got to be willing to risk failure, or looking foolish, as you attempt to implement your ideas.