In the days after Christmas and before New Year's Eve, retailers are giving deep discounts to boost their 2011 numbers and clear out space for new merchandise. This is the ideal time to buy sweaters/ coats/ boots, and anything wintery.
I just went to Urban Outfitters and cleaned up on sweaters. I also have made a killing on Bloomingdales.com. Check out your fave retailer before 12/31 and you will be sure to have a happy new year!