http://www.flickr.com/photos/thomashawk/2311166742/

Update: my own public service announcement

Relevant information for photographers, at least in the U.S:

The right to take photographs in the United States is being challenged more than ever. People are being stopped, harassed, and even intimidated into handing over their personal property simply because they were taking photographs of subjects that made other people uncomfortable. Recent examples have included photographing industrial plants, bridges, buildings, trains, and bus stations. For the most part, attempts to restrict photography are based on misguided fears about the supposed dangers that unrestricted photography presents to society.