[cstaylor]

Well, if you are a badass in your particular field, you can always turn it around on your boss: "Hmmm... I wonder how long they'll keep YOU once I'm gone".

This only works if others higher-up in the company know about your skills... fortunately, most good bosses recognize talent and will find a way to accomodate you (if not, hit the bricks and find a better job... bonus points if its with a competitor)