The purpose of this annual event at the former World Financial Center is twofold: families can admire exquisite structures designed entirely from cans of food (past creations have included giant electric mixers, rocket ships, cartoon characters and castles), and each can will be donated to City Harvest at the end of the exhibition. While the event is free, attendees are encouraged to contribute a can or two of their own to feed the hungry. At the last competition, 91,000 pounds of canned goods were donated; the organization will no doubt be hoping to top that this time around. Displays will be up at Brookfield Place through November 13.