Imagine a man named Jim. He's applying for a job at Google. Jim knows that the odds are stacked against him. Google receives a million job applications a year. It's estimated that only about 1 in 130 applications results in a job. By comparison, about 1 in 14 high-school students applying to Harvard gets accepted.

Jim's first interviewer is late and sweaty: He's biked to work. He starts with some polite questions about Jim's work history. Jim eagerly explains his short career. The interviewer doesn't look at him. He's tapping away at his laptop, taking notes. "The next question I'm going to ask," he says, "is a little unusual."

You are shrunk to the height of a nickel and thrown into a blender. Your mass is reduced so that your density is the same as usual. The blades start moving in 60 seconds. What do you do?

The interviewer looks up from his laptop, grinning like a maniac with a new toy.

"I would take the change in my pocket and throw it into the blender motor to jam it," Jim says.

The interviewer's tapping resumes. "The inside of a blender is sealed," he counters, with the air of someone who's heard it all before. "If you could throw pocket change into the mechanism, then your smoothie would leak into it."

"Right… um… I would take off my belt and shirt, then. I'd tear the shirt into strips to make a rope, with the belt, too, maybe. Then I'd tie my shoes to the end of the rope and use it like a lasso."

Furious key clicks.

"I don't mean a lasso," Jim plows on. "What are those things Argentinian cowboys throw? It's like a weight at the end of a rope."

No answer. Jim now realizes that his idea is lame, but he feels compelled to complete it. "I'd throw the weights over the top of the blender jar. Then I'd climb out."

"The 'weights' are just your shoes," the interviewer says. "How would they support your body's weight? You weigh more than your shoes do."

Jim doesn't know. That's the end of it. The interviewer begins ticking off quibbles one by one. He isn't sure whether Jim's shirt—shrunken with the rest of him—could be made into a rope that would be long enough. Once Jim got to the top of the jar—if he got there—how would he get down again? Could he realistically make a rope in 60 seconds?

Jim doesn't see where a word like "realistic" comes into play—unless Google has a shrinking ray.

"It was nice meeting you," the interviewer says, extending a still-damp hand.

***

Jim isn't quite imaginary. He's a composite. For the last eight years I've collected interview questions. The blender question is real. Several Google interviewees recounted to me what happened when they came up against it. And though Google doesn't comment on the specifics of its hiring process—it likes to maintain an air of mystery, which has led to a cottage industry of samizdat Google questions passed among hopeful future employees and curious outsiders—former and current Google HR specialists have shared rather freely with me what it is that motivates the way they interview job candidates.

We'll get to the longer answer, but the short answer is that Google isn't looking for the smartest, or even the most technically capable, candidates. Google is looking for the candidates who will best fit Google.

That's tougher than it sounds. And the dilemma Google faces is emblematic of our depressed knowledge economy. We live in an age of desperation. But in our current economic climate, employee screening has become more, not less, important. In a boom, companies could afford to be cavalier about hiring. If a worker didn't fit, he or she would soon move on. Today, employees cling to jobs like limpets to wet rocks. The only way to get rid of someone is to fire him (an increasingly fraught maneuver in our litigious society). Thus, the flood of job applicants has to be strained more finely than ever before, as even unsexy firms find themselves with multiple well-qualified applicants for each position.

How are companies coping with this new environment? In September 2009, the Labor Department reported that job seekers outnumbered job openings by 6 to 1. These unemployment numbers have spread riddles, loaded questions and multiple-interview marathons across the corporate food chain, into mature and less cutting-edge industries. Each year Glassdoor.com compiles a list of "oddball" interview questions (puzzles, riddles and the like) reported by members. In the most recent list, only about a quarter of such questions came from tech firms. The rest were from mainstream corporations, from Aflac to Volkswagen.

"If you could be any superhero, who would it be?"

"What color best represents your personality?"