The 1973 science fiction film Soylent Green portrays a dystopian future were people survive on revolutionary foodstuff, but there's a kicker. In the final scenes, we discover that soylent green is people! Now comes a new diet consisting of substances different from what we think of as food. It's all the brainchild of Silicon Valley entrepreneur Rob Rhinehart, whose Kickstarter campaign to raise $100,000 ended up with more than a million. Science writer Brian Merchant lived on Soylent for 30 days. He's the senior editor of Motherboard, the science and tech website published by Vice.