Darkness reigns no more
Essentially, it's single images run through the tunnel, so that as the train passes with viewers inside, our persistence of memory causes the images to animate into a moving image (like the way frames of film work, or a flip book). Check it out at the Submedia website.
Now, being a regular commuter myself, I have found the subway to be a real dead-zone. I often forget my book, then rush past the free dailies, failing to snag one before popping through the turnstile and onto a train. That's when I find myself caught for the next thirty minutes with nothing to stimulate me but the paltry few poster ads which I have read (and mentally critiqued) about a thousand times before. So what do I do? I stare out the window, into the black void of the tunnel or back at my own reflection. For thirty minutes.
Now, I love ads. I love the camera work (either still or moving) I love the animated logos and I love the typography. Even when it's bad, I enjoy tearing it apart, finding the kernels, and mentally rebuilding it. Now, I truly hope that advertisers using this medium won’t simply treat it as another single plane field like a television set, but instead choose to make use of the space, crossing from one side of the train to the other, or referencing the tunnel in which the ad lives.
But hey, I’m just happy I won’t have to stare at the back of someone’s head for half an hour.