Elon Musk's brother, Kimbal, cofounded a high-tech company for a very low-tech product—spinach. And also chard and mustard greens and anything else that can be grown in an old shipping container outfitted with $85,000 worth of high-tech farming equipment. Called Square Roots , the idea could shake up the way we think about farming and food production. Its genesis comes from an unlikely source: weed. " Cannabis is to indoor growing as porn was to the internet, " says its CEO and cofounder, Tobias Peggs.