Million dollars, but you turn into a magical creature, but you are the only magical creature on earth. You may or may not be hunted and/or experimented on because of this, depending on how you handle it.
You get a million dollars but every week you will be mysteriously mutilated with scissors by an unknown entity. It hurts, but is never ever life-threatening even if it looks so. It heals completely at the halfway point of the week.