Grad students Mike Barry and Brian Card have produced an impressive new set of interactive visualizations of Boston's subway system. It's worth having a look for yourself here; much is lost when these are reduced to a screenshot. They've looked at key transit metrics like travel time, passenger volume, vehicle delay, and station congestion among other topics, all drawn from MBTA's open realtime data, in a style inspired by the content-first approach of design guru Edward Tufte.
The image below is an example, showing the time of point-to-point trips of individual trains through the day. In this chart, the steeper the slope of the line, the longer the trip took. Scrolling through the day, the effect of the peak periods becomes apparent as the quantity and steepness of lines increases.
Another example of the type of work skilled information designers can produce when public agencies make their data available.