A lifeguard at a good surf spot.
I used to be one, along with another guy, two of us on duty all the time, and had a great boss that would come out onto the pier, where our stand was, to check on us from time to time. He allowed one of us to be patrolling the water (on the water) whenever we wanted. Of course there is only one way to patrol the water, on a surfboard. And of course the rescue board was too big, bulky, and slow to adequately do patrolling. Four of the best summers of my life.
Need I say anything else?