This is a really satisfying animation to watch. The thick, bunched-together lines of ships all turning the corner at some cape or strait really show you how the cargo is moving.<p>Does anyone else understand the UI? It does not make sense to me: the giant "play" button blocking the middle of the display seems not to play, but to stop playing, replacing the moving-dot animation with colored streaks. Clicking it again causes the map to zoom out! Then I reloaded the page, and this time instead of trying to click the giant "play" button, I clicked "options", which did not bring up any options, but did move the "play" button out of the way to the corner.