This week, Rihanna hit the vacation spot Sardinia, where she got just a little wild and crazy -- and we have the Twitpics to prove it. Late one night, the 'S&M' chart-topper sent a spitfire series of what we assume to be drunk tweets to her 7 million followers, many with the hashtag #boatsandhoes, and each contained hilarious pictures of RiRi partying it up. In one particularly funny photo, it seems that the naughty Barbadian put stickers on top of an unknowing bald man's bare head, and made sure to tell her Twitter followers to keep it on the DL with one finger to her lips. Also this week, Grace Potter partied on a boat, Camryn popped into a photoshoot, and Romeo shared a Twitpic of himself shirtless while he was sick in bed (we bet).