Not sure if this has bee posted here before, but here goes.
Stumbled across this interesting little article recently while surfing the net. It's apparently an ad from a 1949 issue of Modern Mechanix, advertising a 'breathing balloon' for women, designed to improve lung capacity and (supposedly) 'develop' the female figure.
http://blog.modernmechanix.com/2006/03/29/breathing-balloon-for-big-breasts/
The image included in the article isn't especially tantalizing, but the concept is intriguing nonetheless. Could make good fodder for a story.