Here we are in the busiest shopping week of the year. We are spending billions - $48.1 billion to be precise, according to retailers' predictions - on gifts for each other, on food and drink to load up our Christmas tables, and on bars, restaurants and fast food to celebrate the festive season. Thursday is expected to be the busiest day of the week, but peak frenzy will be the fifteen minutes after 1pm on Friday, according to the National Australia Bank, which expects to process 360 transactions per second in that brief interlude. To avoid the rush, shoppers are advised to brave the aisles in the early morning or late afternoons.