After Charlotte hails a cab she tells Stephan it helps to show a little leg. Carrie does it in Abu Dhabi, when they're trying to get a cab to the airport in Sex and the City 2. She was mimicking Claudette Colbert from It Happened One Night which she & Big watched after Stanford & Anthony's wedding. A little white noise. Samantha did it in Season 4 ep 9 Sex and the Country.