I recently bought a couple of hundred posters of Earth from space which I've been putting over and next to freeways along the west coast. Some I post by themselves - like the flags that went up after September 11th - and some I put up with messages. I want to make this action as effective as possible, so I'm turning to you for help.
Think of the most effective message(s) to go along with (or without) pictures of our planet and send them to me at email@example.com . Best one wins a thousand dollars and will be seen by a million people: at least. 2nd and 3rd place winners get $500 and $250 and will be seen by a couple of hundred thousand, if not more. Deadline is March 15th.
Here is how I make the signs. I attach them to fencing using bungee cords and duct tape: takes about five seconds. Sometimes they'll stay up for hours, sometimes days or even weeks. Because of the ease of signmaking and the density of traffic, a sign that takes ten minutes and five cents to make can be seen literally hundreds of thousands of times before coming down. So long as it's easily detachable and posted safely (on the inside of the fencing rather than the outside) it's just as legal as putting up a flag. And it's a hell of a lot of fun.