Everyone knows that there are names for groups of animals, a pride of lions, a raft of otters, or a bed of oysters etc. So I got to thinking one day and wondered what do you call groups of people all engaged in a specific activity?

Example: When I drove along Highway One along the California coast yesterday from Santa Cruz to Half Moon Bay, I passed a beach where there were 20 kite surfers catching the wind and speeding across t...