Designer/architect Wholman made this fence out of discarded, recycled road-signs in Greensboro, AL, along with the local YouthBuild chapter (a Department of Labor project "that provides low-income young people a chance to study for their GED and acquire trade skills, all while earning a small stipend for their labor"). He's posted an Instructable so you can do it, too (this may just be the coolest fence I've ever seen).
The local county and state highway engineering offices donated old road signs, which we then cut, sanded, filed, and drilled to create pickets. Using jigs and a self-organized assembly line, the students manufactured nearly a thousand pickets for roughly 225 linear feet of fencing. By cutting and randomly re-assembling the signs, the graphics were broken and rebuilt into a new collage of abstract symbol and color.
Sad endnote: Congress has shuttered YouthBuild, even though "YouthBuild generates $9 of economic output for every $1 spent on it."