Professor Greg Tew, by incorporating a monomer with a cobalt ligand
into a block copolymer, has produced a magnetic material that
increases the density of information storage. This is considered "the
first report of a processible, ferromagnetic polymer" that is both
prepared and magnetic at room temperature according to a leading
metal-containing polymer expert.

Details at: http://pubs.acs.org/cen/news/87/i34/8734news6.html