New York Times: Stephen Colbert doesn’t have his own television show yet, but he continues to find unexpected (and increasingly esoteric) ways to remind people that he will soon be returning to the airwaves. The incoming star of CBS’s “Late Show” made an unheralded appearance on Mpact, a public-access television station in Monroe, Mich., during which he interviewed a local resident, Marshall Mathers, who is better known as the rapper Eminem.