We are obsessed with the fact that OPI is collaborating with Mariah Carey on a limited-edition set. Singer of high notes, and a lady with curves, Mimi is once again doing big things. We just can't wait to see what her collection will be all about. Glitter? Butterflies? 3-D Rainbows? The possibilities are endless. All we know is once this collection hits shelves in January, it will be one sweet day.