How to survive the January sales

Why are we such suckers for a 50% off sign or an 'unrepeatable' special offer? And how can we avoid buying stuff we don't really need? The turkey has been eaten, the presents unwrapped and the Queen's speech watched. Which can only mean one thing - it's time to get ready for the post-Christmas sales. No matter how much we've indulged over the festive season or how many gifts we've received, there's something about the chance to bag a bargain that lures us out into the cold and damp, whatever we ...