At the tender age of 4, a light bulb went on over Johanna's head. Literally. Although born in New York, she moved with her family when she was three to a tiny Mexican town where milk was still delivered on donkeys. The only blond in town, she really stood out on the Cinco de Mayo parade float she rode, patting out tortillas. One night, on a bare plywood stage lit by naked light bulbs, she did the twist for her kindergarten recital in front of a gaggle of adoring parents. And even if a star was not born, the glow of that little bare bulb never left her. When she was five she moved to Mexico Cit...