When someone tells me I'm not allowed to take a picture, I take it as an affront and a challenge. I haven't looked into the actual legality of the situation yet, but I'm pretty sure there's nothing wrong with photo-
graphing the former TWA Terminal at JFK (above), as I tried to do before I was stopped by security, or in the various stores, museums, and establishments who routinely tell you, "Photography is not allowed". With the advent of tiny digital and cell phone cameras it's pretty hard to enforce anyway, but here are some samples of my recent surreptitious iPhone camera work.
This from the revelatory August Sander show at The Getty (photography not allowed), about which I'll write more later. The title for this picture is "The Photographer after a Nap" so it's an unusual self-portrait!
This from Katsuya - a new-ish Philippe Starck designed restaurant in Brentwood. The tricky thing here was that Robert Downey Jr. was sitting at a table just to the left of the frame so I was trying to get the graphic on the wall while respecting his privacy as a diner. However, I'm sure he thought I was pretending to photograph the wall while really trying to snap him!