Kathy Griffin lives her life on the D-list, but she recently had an A-list moment with her idol, Cher. “I was shaking,” Kathy tells In Touch of meeting the singer at her Las Vegas concert on August 16. “She was delightful and what a great ass she has! It was a real girls’ weekend in Vegas.” Their half-hour chat was “heaven,” says Kathy. “I am always star-struck — especially in the presence of an icon like Cher who just happens to be very friendly and fun!” Kathy got her backstage pass by striking a deal with pal Rosie O’Donnell: In exchange for the introduction, Kathy’s ex, Steve Wozniak, agreed to take Rosie to the prestigious TED conference in February 2009. “I hope Cher’s not insulted that she was a part of the trade!” “I think I made Cher laugh a couple of times. Maybe someday she’ll come see me [perform in Las Vegas] at Mandalay Bay. A girl can dream, can’t she?” says Kathy.