Roll-front wooden lockers were a gift to the catarrhal terrorist. You spend half an hour hacking up phlegm then select a locker. You slightly raise the front and then carefully dribble extremely glutinous phlegm - the Camel Yocker - into such a position that the locker front, when lowered, rests in it. Any subsequent raising of the locker front produces a glistening, nauseating curtain of yocker strands, preventing access to the locker's contents. If you were really lucky, you could distract the locker's owner at exactly the right time. He would then reach in without looking, pushing his hand through the napalm-like yocker waterfall.