Abstract: A display member (10) comprising a housing (14) having a chamber (12) with a viewing face (16) and a lamina member (24) movably mounted within the chamber (12) to be movable into a first position in which one face (26) of the member (22) is in face to face contact with the viewing face (16) and a second position in which the one face (26) of the member (24) is out of contact with the viewing face (16) and the other face (25) is in face to face with a rear face (15) of the chamber (12) spaced rearwardly from the viewing face (16), a drive (22,20) being provided to produce an attractive and/or repulsive force between the housing (14) and the member (24) to move the member (24) from the first or second position to the other position wherein no external energy need be provided to maintain the member (24) in the first or second position, an opaque fluid filling the chamber.