You can do a LOT of shopping here, so be careful with your credit card- you may come home to an unpleasant bill! One of my favorite places in London, especially all decorated at Christmastime, there's space for budget and luxury shoppers alike (though for the high-end things you may have to step off to Bond Street). Beware during the evening rush hour, though- the tube gets insane, and don't even think about going into Primark during this time!