I saw stumbled across these links:
http://www.roninrome.com/%20shopping-dining/inexpensive-shopping-in-rome
http://intransit.blogs.nytimes.com/2009/07/28/bancarelle-bargains-in-romes-roaming-markets/
I am going CRAZY because shopping is my favorite hobby next to putting on lipgloss on overly crowded Roman buses (reference to previous post). Does anyone know about these? Do they tend to stay in one place or are they mobile stalls? Do they operate every day of the week? Is it really worth the hoopla?