ONCE a week, on Sundays, Hong Kong becomes a different city. Thousands of Filipina women throng into the central business district, around Statue Square, to picnic, dance, sing, gossip and laugh. They snuggle in the shade under the HSBC building, a Hong Kong landmark, and spill out into the parks and streets. They hug. They chatter. They smile. Humanity could stage no greater display of happiness."