In Greece, more than 21 percent of the working-age population is jobless. For Greeks under age 25, the rate is more than double that.

Some young Greeks are frightened that the economy, now in free fall, will take years to recover, so they're leaving for jobs abroad. A few entrepreneurs, however, are trying to start businesses during the worst recession in decades.

A magnet for these young entrepreneurs is CoLab, a business incubator in a weathered building near the Athens Cathedral in the city center. CoLab opened in 2009, with just one occupant — a Spanish travel writer.