I've gotten that one a few times, and I always write something that only contains the string 'Fizz' once and 'Buzz' once (i.e., doesn't say 'FizzBuzz' separately, just uses the same logic to print 'Fizz' and 'Buzz' both), because I figured that was partly the point; otherwise it would be "print 'Zarples' for both multiples". I've been told that it's the first time the interviewer saw it done that way, and now I see several replies here that also would take no modification to use 'Zarples' instead of 'FizzBuzz'.

No point to this, I guess, other than that even something as simplistic as this is open to interpretation.