Interactive maps can both be functional and, when combined with data, tell a good story. Kiln released this data-driven map (make sure to hit the play button) to show the routes of every cargo ship moving about on the high seas in 2012.
How something like this is created can be mind-boggling. Kiln has a service called Flourish that helps with the lifting and we recently shared Observable, which has a similar aim. Sarah wrote up an entire tutorial on creating serverless data visualizations.