the unbelievably prolific designer enzo mari has created some truly beautiful shelving in all sorts of materials, including the metal systems shown above, manufactured by robots in italy. he's also designed bookcases in wood and cardboard. so, what does mari use in his own home? none of the above. he uses the out of production glifo, a super-flexible polypropylene system he designed in 1967 (shown below, from the book "at home with the makers of style").