Tuan C. Nguyen, writing for Smithsonian:
One particularly intriguing proposal that futuristic-minded engineers have batted around since the 1960s is the notion of a high-speed train that can transport and pick up passengers at various stops along the route without ever having to actually, you know, stop. A true express train from say, New York to Los Angeles, would offer a much shorter overall commute time and, without the constant stop-and-go, cut down significantly on fuel costs for train operators, which maybe—just maybe—would translate to lower fares for all.