All things must come to an end. While admiring Rihanna's various bikini-related activities from her Hawaiian vacation took up most of our time last week, we must now move on to alternative time-wasters. But not quite yet! RiRi is back in the continental United States, but the photos of her lovely and extremely tiny bathing suits abound. Check out a collection of her best, and applaud this brave woman for never fulfilling the urge to throw on a pair of gym shorts.