Rihanna recently debuted an edgy new hairdo. But when the "We Found Love" singer hit the red carpet for the Japan premiere of "Battleship" Tuesday, she opted for a comfy, cozy look, sporting a bright blue pajama-esque ensemble.
RiRi's not the only star who's donned PJs for a formal affair. Jessica Alba, Matt Damon and other celebs have been spotted out and about in their finest sleepwear.
Who else has participated in the trend? Click through our gallery to find out!