How to hack a nation's infrastructure

I'm watching a live video feed of people visiting a cafe in London. It's a small, busy place and is doing a good trade in tea, coffee and cakes. That woman has dropped some money. A child is running around. Later, another customer thinks they have got the wrong change. via Pocket http://www.bbc.co.uk/news/technology-22524274#sa-ns_mchannel=rss&ns_source=PublicRSS20-sa