This hack shows how to modify an old CB radio to broadcast on the channels that fast food restaurants usually reserve for their drive-thru windows. Although we here at MAKE don't condone this particular use, it's still a valid way of modifying existing systems to create new opportunities for interaction on open frequencies.
Phone Losers of America [via]
http://blog.makezine.com/archive/2008/03/use_a_cb_radio_to_order_a.html