Insight: No smoke, plenty of fire fuels e-cigarettes

By Kate Kelland and Ben Hirschler LONDON (Reuters) – Puffing on slim metal tubes loaded with pale yellow liquid, two London businessmen say they have between their lips a cure for what the U.N. calls "one of the biggest public health threats the world has ever faced". Electronic cigarettes are the future, they argue. Cheaper, cleaner and cooler than smoking, "vaping" – using a vaporizer to inhale nicotine infused with exotic flavors ranging from pina colada to bubblegum – will spell the end of tobacco. …