March 13, 2005 FRANK RICH The Greatest Dirty Joke Ever Told T was two and half weeks after 9/11 that I heard the dirtiest joke I'd ever heard in my life. New York was still tossing and turning under its blanket of grief back then. Almost no one was going out at night to have fun, a word that had been banished from the country's vocabulary. But desperately sad people will do desperate things. That's my excuse for making my way with my wife to the Hilton on Sixth Avenue, where the Friars Club was roasting Hugh Hefner. Someone had decided that the show must go on. A crowd materialized out of nowhere to pack a vast ballroom in an otherwise shadowy and deserted Midtown. On the dais were not only the expected clowns old (Alan King) and young (Jimmy Kimmel) but a surreal grab bag of celebrities out of Madame Tussauds: Dr. Joyce Brothers, Ice-T, Patty Hearst, Donald Trump. "God Bless America" was sung by Deborah Harry.