Do you have what it takes to handle the World's Toughest Job? It requires more than 135 hours per week, constant mobility, keen coordination and adept communication. There are no breaks, no holidays off, and there is no pay.

Mullen, an advertising agency in Boston, posted a fake "Director of Operations" job listing online and in newspapers. The ad got 2.7 million impressions from paid ad placement, but only 24 people responded, according to Ad Week. Each of those people then sat down to interview for the job and all were shocked at what was required of them: no sitting, no vacations, no guaranteed sleep and zero money.

"Is that even legal?" one applicant asked. "Nobody is going to do that for free!" another responded.

But billions of people do all this each and every day. When the applicants found out just who holds the title of "World's Toughest Job," some were brought to tears.