Sing adds 5 to the city he is in when he casts it. This random idea occurred to me when my younger brother built him for his first time. He liked sing, but was somewhat disappointed that it didn't do anything. In addition to livening up the somewhat dull hero, it would be great for far flung Lanune expansions. Sing for a few turns and you'll have the fat cross fully accessible for building pirate coves and the like. Not exactly the flashiest thing, but certainly useful. Anyways, just throwing it out to see if it sticks.