Speed limit sign along the Vasona industrial lead through Campbell, California. Railroad speed limit signs indicate whether the speed is going up or down; I wonder if this could be usefully applied to roads?

Shot with the Nikon D70s and the 18-70mm f/3.5-4.5 zoom at 18mm, ISO 400, f/10, shutter 1/800 sec. Exposure, contrast, highlights, and levels adjustments in Aperture.