EDIT: for the commenters - I agree an hour is too much. Whacking out FizzBuzz in 15 minutes could have its place :) When I experienced FizzBuzz as a candidate

EDIT: for the commenters - I agree an hour is too much. Whacking out FizzBuzz in 15 minutes could have its place :) When I experienced FizzBuzz as a candidate I was coding onto a projected screen, and the test involved writing unit tests and doing a final refactoring step into something "reusable". It took the best part of an hour. The instructions themselves required a good 5-10 minutes of reading/parsing to understand exactly what was expected of you.