Ok, this is a really cool project. Timo Arnall, Jørn Knutsen and Einar Sneve Martinussen (from the Oslo School of Architecture & Design) rigged up a device equipped with a series of lightbulbs to display the strength of WiFi networks. Then they wandered around Oslo and took long exposure photographs that revealed an invisible topography of wireless networks. The YouTube video that they made is must watch.
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