Somehow, I found this three-year-old Coding Horror article about the FizBuzz programming test; it's a very simple programming problem, yet it turned out that a majority of the people applying for a programming job were not able to solve it.
Also interesting is that many people in the comments-section still got subtly wrong solutions – by not carefully reading the requirements.
I suppose many of the job-applicants who could not solve FizBuzz still got jobs in that field, somewhere. What does that mean? Would they just be very slow, that is, could they still solve it after many iterations, debugging and what not? Or is there a sufficiently large segment of programming jobs that put such limited emphasis on algorithms that they can get away with it?