Mad Man historical note:
I was doing some wikipedia research on all the writers/artists who were working in Manhattan after WWII from the late forties through early sixties. I'm fascinated with the image of such a tight concentration of talent that didn't flourish until later.
So this list includes novelists William Gaddis (PR guy), Joseph Heller (advertising copywriter), Edward Gorey (book design), Diane Arbus (fashion photography), Stanley Kubrick (photographer for Time), Andy Warhol (fashion and catalog illustration) and many others. Anyway, following the link from Heller I came across this bit about suspense novelist Mary Higgins Clark:
Soon after (her brother) Joseph died, Clark graduated from high school and chose to attend Wood Secretarial School on a partial scholarship. After completing her coursework the following year, she accepted a job as the secretary to the head of the creative department in the internal advertising division at Remington-Rand. She soon enrolled in evening classes to learn more about advertising and promotion. Her growing skills, as well as her natural beauty, were noticed by her boss and others in the company, and her job was expanded to include writing catalog copy (alongside future novelist Joseph Heller) and to model for the company brochures with a then-unknown Grace Kelly.
Cool, huh? Sort of half Peggy and half Joan. Clark later went on to snag the glamour job of the era, Pan Am Stewerdess, before she got married.
According to one memoir I read, guys like Heller and Gaddis were allowed to work on their novels in the morning and do their regular jobs in the afternoon.