Charlize Theron showed off her smoking hot bikini body during a day on the beach in Hawaii on Monday. The actress sported a striped top and sunglasses while taking a dip in the ocean, then retreated to the sand to sunbathe with a friend. Charlize is likely using her relaxing island getaway to ring in the new year; she, along with her mother, Gerda, and young son, Jackson, were last spotted in Hawaii back in August when they celebrated Charlize's 38th birthday. Needless to say, it's been a big year for the Oscar winner, who filmed two movies — A Million Ways to Die in the West and Dark Places — and made time to show support to causes close to her heart, especially in her native South Africa. Charlize spoke at a press conference about the fight against HIV and AIDS there in November and most recently, she joined Bono, Bill Clinton, and President Barack Obama at the official memorial service for Nelson Mandela.