Mind the Gap

What does "mind the gap" - familiar to anyone who has ridden the London Underground, a.k.a. "the Tube", have to do with coffee and power? It turns out, quite a bit. Starbucks' largest metropolitan deployment outside the US - and the largest in Europe by far - is in London, with ~250 stores. Starbucks has become a very familiar English site, indeed. On the technology front, Starbucks has always been an early adopter and even a driver of new technologies: