Its ridiculously cold outside right now. And with news that we're set to have the harshest of winters for, wait for it, one hundred years together with the prospect of bingeing on mince pieces and cheeseboards throughout the entire month of December - baring your midriff probably doesnt seem the most obvious of choices - but think again. Stylish stars from Diane Kruger (seen here wearing Spring/Summer 2013 Rochas) to Christina Ricci (wearing Spring 2013 Richard Chai Love) have been showcasing their abs in recent weeks in a very varied selection of outfits. But how do they avoid looking like a High school cheerleader? Will you be keeping your look casual like Miley Cyrus or updating winter's printed PJ's a la Rihanna? And what are the rules? Click through our gallery above to find out!