Penelope Cruz is secretly obsessed with karaoke and throws sing-along parties for her Hollywood superstar pals. The actress insists most A'listers cringe at the thought of indulging in the hobby - but love it once they've given it a try. Cruz says, "I have a machine at home. Sometimes I do karaoke parties: everyone arrives saying they're not going to sing, but everybody sings. They all say, 'I'm too cool for karaoke,' and then they are fighting for the microphone."