MIHOKO HAKATA, a freelance illustrator and recent art-school graduate, ducked into a coffee shop in Midtown Manhattan last week, desperate for a jolt of energy. She had work to do. But as she removed her materials from her backpack, it became clear that the energy she was seeking could not be found in a cup. She had a more pressing need: to find a power outlet for her laptop computer, whose battery had died. "I realized they have this," said Ms. Hakata, a 29-year-old Tokyo native, as her hand slipped beneath a table to deftly plug her I.B.M. ThinkPad into...