We've seen WiFi detectors used for various DIY projects before, but none quite like this rather ambitious project cooked up by Norwegian designers Timo Armall, Jørn Knutsen, and Einar Sneve Martinussen. They built a four-meter long WiFi-detecting rod that boasts 80 LED bulbs and carried it around various neighborhoods in Oslo, picking up signals of various strengths from nearby WiFi networks all the way. That's only the half of it, though. The real kicker is that they also captured the whole thing with long-exposure photographs to effectively paint the "invisible terrain" of WiFi networks with light. Head on past the break for a video, and hit up the source links below for a closer look at the entire process.

[Thanks, Christer]