If there's one thing we've learned about our favorite pop stars, it's that they love their social media. This week, Bow Wow gave us a sneak peek onto the set of his 'Sweat' video, featuring Lil Wayne, with a black-and-white shot of himself and Birdman hard at work. Also this week, Demi Lovato showed off a goofy souvenir she got while traveling, and boy does she look cute in that sock monkey hat! Sara Bareilles shared a drunk Twitpic, which really had us laughing, Christina Perri hung out with the Beatles (really!) and JoJo made a joke about having a much older boyfriend -- obligatory photo included. See Twitpics of your favorite stars from this week!