As part of a plan to attract advertisers who ordinarily shy away from the anything-goes atmosphere of social-networking websites, is launching a comedy section that will feature webcastsfrom the national chain of Improv comedy clubs. The primary sponsorwill be Pepsi-Cola North America's Sierra Mist brand. MySpace had previously launched sections devoted to movies, music and books.Several individual comedians have become virtual celebrities onMySpace, including Dane Cook who reportedly has amassed 1.34 million"friends" who view his routines on the site.