On Tuesday and Wednesday as Cameron Diaz wandered around the New York set of The Other Woman, it looked as though she may have been taking it to the next level... with a knuckleduster. But fans of the 40-year-old actress can relax: it was just an iPhone case, tailored to make the phone easy to carry and made famous by Rihanna earlier this year... and anyway, Cameron was too busy giggling to be dangerous.