Below is the current open development API key. It may change at any time. This key is open for all developers to use in development and testing. DO NOT go into production using this key! Register for an account and request a key of your own on realtime.mbta.com. There is no cost. As of 5/11/13 the open development API key is: wX9NwuHnZU2ToO7GmGR9uw