This is so cool
http://www.msnbc.msn.com/id/4356095/
excerpt:
Only men learned to read and write Chinese, and bound feet and social strictures confined women to their husband's homes after marriage. So somehow -- scholars are unsure how, or exactly when -- the women of this fertile valley in the southwestern corner of Hunan province developed their own way to communicate. It was a delicate, graceful script handed down from grandmother to granddaughter, from elderly aunt to adolescent niece, from girlfriend to girlfriend -- and never, ever shared with the men and boys.
So was born nushu, or women's script, a single-sex writing system that Chinese scholars believe is the only one of its kind.