I remember hearing that now that you mention it. I never actually used a payphone but I remember seeing them at the mall. Theres a pdf somewhere out there that tells you how to get into the debug menue of the vending machines that had the single column of buttons and the small red LED screen. Once your in the debug menue you can tell the machine to dump the change. I got into the menue but I was afraid to actually let it do that so i just left the machine in debug mode. Fun times at walmart.