She may be bonkers/annoying, but we’re strangely fascinated by Lady GaGa. So we had mixed emotions when we heard that she’s going to be making a guest appearance in Gossip Girl. We don’t know much about what the Paparazzi singer’s guest slot involves as it’s all being kept under wraps, but Penn Badgley, who play hot Dan Humphrey, has revealed: "I don't want to give away too much, but she will perform a little bit. And it is involved in my story line." Ooh!