a message/ad carried by a person composed of two boards on both sides.
A crazy guy was going down the street in a sandwich board saying that the wold was going to end
by The hardest button to button February 14, 2010
A sign comprising of two boards strapped to a religious man carrying a message of doom.
A sandwich board carrying the message "You're a loser - Craig Jackson"
by Geordie racer October 14, 2011