Klaatu Barada Nikto

This was the first time I had attempted a prank like this, so I expected the control box to be locked, and the programming functions password-protected. I was wrong. First of all, the control cabinet had no lock. Swinging open its door, I found a deliciously inviting handheld keypad, then took a wild guess and pushed a button labeled STOP. The display on the control box flashed ENTER PASSWORD. I was about to give up in disgust when I noticed that someone had written the password in large Sharpie lettering above the box.
I entered the password, and lo! The sign ceased its flashing and turned itself off. SELECT FUNCTION, the keypad blinked, and great was my joy!
With only a few minutes of road sign hacking, I had programmed an homage to the 1951 sci-fi film The Day The Earth Stood Still, the phrase that was used to stop Gort, the robot in the film, from taking over the world.
As for the modified messages, they stayed up nearly two days before someone finally turned both signs off for good. And thus my mission was complete: By programming that phrase, the machines were unable to take over the world.more
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