I never noticed this while I was in the new Minato Mirai subway but it sounds CREAPful enough for me....via the dottocomu blog:
"A glimpse of the future: interactive ads?
.....an experiment into interactive advertising in the new Minato Mirai subway linking Tokyo's Shibuya with Yokohama: it will have a system set up in a concourse tunnel that detects pedestrian movements via a brace of TV cameras and uses the information to alter the images (art, local information, and advertising) projected on the tunnel walls..."
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