The Ship Map. Global shipping via 250 milion data points. Winner at the 2016 Information is Beautiful Awards. site 
First place in interactive category. ShipMap.org by Duncan Clark & Robin Houston at Kiln. site
You can see movements of the global merchant fleet over the course of 2012, overlaid on a bathymetric map. You can also see a few statistics such as a counter for emitted CO2 (in thousand tonnes) and maximum freight carried by represented vessels (varying units).
You can pan and zoom in the usual ways, and skip back and forward in time using the timeline at the bottom of the screen. The controls at the top right let you show and hide different map layers: port names, the background map, routes (a plot of all recorded vessel positions), and the animated ships view. There are also controls for filtering and colouring by vessel type.