http://news.yahoo.com/s/ap/20061010/ap_on_...eople_streisand The most riveting moment of Barbra Streisand's Madison Square Garden concert was one of the only unscripted ones. Streisand endured jeers as she interjected a political skit into Monday night's show, exchanging zingers with a celebrity impersonator playing George Bush as a bumbling idiot. Though most of the crowd offered polite applause during the slightly humorous routine, it went on a bit too long, especially for those who just wanted to hear Streisand sing. "Come on, be polite!" the well-known liberal implored. But one heckler wouldn't let up. And finally, Streisand let him have it. "Shut the (expletive) up!"; Streisand bellowed, drawing wild applause. "Shut up if you can't take a joke!"