The Massachusetts Bay Transportation Authority (MBTA), also known as "the T", has an API for querying information about service performance.

1. Clone this repository
2. Install Ruby if you don't already have it
3. Follow the instructions on http://realtime.mbta.com/portal to get an API key (there's an open development key you can use to get started, but please don't abuse it)
4. Run API_KEY={your api key} ruby last_train.rb