It is a pouch called "Diapees and Wipees" that is designed
to carry a few diapers and a travel pack of wipes. The pouch
then fits into your purse.
It is available in lots of cute fabrics!
http://www.diapeesandwipees.com/html/products.html
http://www.windsorpeak.com/dc/user_files/28298.jpg