Do your customers know each other? You are a common bond. Can you facilitate opportunities for them to interact? The concept of the "mesh" of crowd-sharing is alive and well.
NeighborGoods.net makes it easy for real-life neighbors to meet and share ladders, lawnmowers, and helping hands. Airbnb.com helps people find space (a house, a room, a sleeping bag) in other people's homes. Once upon a time, Saturn held annual reunions and factory tours for new car buyers.