But now there is the danger of a new form of lock-in. “Cloud computing”—the delivery of computer services from vast warehouses of shared machines—enables companies and individuals to cut costs by handing over the running of their e-mail, customer databases or accounting software to someone else, and then accessing it over the internet. There are many advantages to this approach for both customers (lower cost, less complexity) and service providers (economies of scale). But customers risk losing control once again, in particular over their data, as they migrate into the cloud. Moving from one service provider to another could be even more difficult than switching between software packages in the old days. For a foretaste of this problem, try moving your MySpace profile to Facebook without manually retyping everything.