I wanted to do an Arduino-based project, but ended up with this. Taken with Nikon D90 and Nikkor 50mm f/1.8 D. Processed in digiKam. Shutter speed: 1/60 sec. Aperture: f/9 ISO: 200
The photo is published on Wikimedia Commons under the Creative Commons Attribution-ShareAlike 3.0 Unported License.
Wikimedia Commons: http://commons.wikimedia.org/wiki/File:The_path_of_least_resistance.jpeg