Debt-ridden and hidebound, Europe may be on the verge of a painful breakup. America is still reeling from the 2008 financial crisis. Even China and India -- the new engines of global growth -- seem to be sputtering these days. Worse yet, the usual wonkish prescriptions don’t seem to be working anymore. So we asked 13 of the smartest people we know to give us their one out-of-the-box idea for fixing the global economy. Here’s what they recommend.