The world is full of famous female advertising icons—Betty Crocker, Bounty paper towels' Rosie the waitress and, most recently, Flo, the irrepressibly perky customer service rep for Progressive insurance. Most of these characters have well-known lineages, but one brand mascot is as mysterious today as she was 109 years ago. She has no name. Nobody's sure where she came from. And yet, chances are, more men have looked at the "girl in the moon" than any other famous lady of branding.