A man who stands ankle deep in brutal concrete while charging you astronomical amounts of money for his services. You will spot him easily at your local pub by what appears to be dried birdshit on his shirt. Fear not, it is not bird shit, it is the fruits of his labor. When your specialist leaves, his only guarantee is that concrete gets hard and it will crack.
My Mud Maggot buddy Walter poured only three floors today and made five grand.