Plants and fish in a closed loop on any rooftop or other available space.
Short video, toss in sabotage of pipelines and extreme financial problems, you have a melt-down. See also his book, Why Your World Is About to Get a Whole Lot Smaller: Oil and the End of Globalization.
Cessium for the masses. A good example of why global sourcing of food/services = no control. See Urban Farming above for an antidote.