Universal Studios has become the latest studio to release movies specifically for the Sony PlayStation Portable, a handheld game device that also plays movies in a special format. Universal said Monday it will release six titles on Universal Media Disc (UMD), the proprietary format devised by Sony for the PSP. Sony, The Walt Disney Co. and Twentieth Century Fox have previously said they will release films on the miniature disc. Initially the studios are releasing films that appeal to young males, the audience most likely to buy the portable games device.