San Francisco declared a groundbreaking ban on plastic shopping bags this past spring, but the question still remains: what do we do with the wads of crumpled-up plastic bags now festering in city cabinets and closets? Local found-materials artists and designers propose their most creative bag-reuse ideas at tonight's celebration, which features a bag-themed fashion showdown, house beats from DJ Brent Northey, and an appearance by Supervisor Ross Mirkarimi, who played a key role in the big bag ban's success.