A community exchange is a group, often with a web site) that facilitates exchanges of work or value between it's members.
There a wide range of community exchanges around the world including: - Time Banks - LETS
# Geojson Web Service
Here is an list of index files from various projects that we can draw on a map:
- HourBank - hourworld.org 
- Community Forge sites - github
- Community Forge geojson - sites.json
The Transporter below implement the Geojson Web Service which is designed to make it as simple as possible for existing community currency exchanges to generate geojson files in order to enable a range of map mashups that show the locations of the exchanges: