The popping of the debt-fueled real estate bubble helped trigger the first global recession since the 1930s. But not every bubble is bad. Railroad bubbles in the 1800s built tracks that outlasted the mania. The burst of enthusiasm for space travel that launched the Apollo mission even put human beings on the moon. Here are some of the latest bubbles around the world—some serious, like the rise in farmland prices, some simply Bieberesque.