Necessity gave birth to this invention.  I was using a service to show my bus on a map so I could leave the office just in time with a minimal wait in the cold.  They stopped tracing the MBTA so I had to roll my own web app.

The first screen of this app allows the selection of any tracked bus in the system.  Once a bus is selected all buses on the route are shown on a  map with their positions updated in real-time.

A filter allows only inbound, only outbound or both buses in both directions to be shown.   Bus icons are color-coded by their direction.  Clicking on any stop gives predictions of arrival times and clicking on any bus icon presents the most recent status reported by the bus.

To experience the thrill of real-time bus mapping view the app.