Yesterday we were out at lunch and stopped at the bank drive-thru.  Below is the site that greeted us:

"So what", you say.  Notice the red warning sign on the bottom left of the glass.  No, not the phone number, the international sign of No Guns! 

Does this work?  It must, because why else would it be there?  Besides, in a "Here's your sign" sort of world, some idiot probably tried to rob a bank from the drive-thru!  "Hey," the robber must have thought, "I don't have to get someone to drive the getaway car, I can do it myself using the drive-thru!"  Do you think he was surprised when the girl just walked away and called the police?  "Hey!  Come back!  I'm not finished, yet.  You haven't heard my demands!  Come on...."

I guess international symbols are useful!  I am going to make a few for myself, now that I know they are effective.  Stay tuned....

BTW, the above picture was altered in only one way:  I pixelated the name of the teller, she just works there, it's not her fault.