During the job interview when asked the obligatory question "where do you see yourself in five years?" I always wanted to answer "In five years I'll be your boss's boss. At which time you'll both be fired."
-MilesAhead
The proper way to answer that question is "Sitting in your seat."
And when they ask "And where will I be that you think you'd get my seat?"
Answer that with "What? You don't plan on moving on to bigger and better things, too?"