Pay a visit to Selfridges. No, it's no big deal, and unless you are ready to spend all your vacation budget on a single shoe in the women's department, you'll get tired of browsing around before you know it. Trust me, you are a big performer if you end up sorting the place even half-way through... Quarter way. Make sure you drop by the confectionary and bakery section though. It's a sweet-tooth paradise. Just savor every single moment of the ride, eventhough all you wind up doing is take pictures.