Micromolding in capillaries of polystyrene has been carried out using a poly(dimethylsiloxane) stamp, derived from a compact disk (CD) as master, while heating above the glass transition temperature of polystyrene. The resulting pattern contained a replica of the parallel channels but with an important difference that trenches of width approximately 30 nm were found in between. The nanotrenches in polystyrene could be filled with metals by physical vapor deposition and electroless plating. This method finds potential applications in nanoelectronics and nanofluidics.