The rat race is a drag, fighting the rush hour is a headache, and sitting in a drab cubicle all day can be life draining. More and more firms are going virtual, allowing their workers to work from home full time, or come into the office only a few times a month. It makes sense. Workers are happier and get to choose their hours, which—as we recently reported—makes them more productive. Employers benefit too by saving costs on office rent and supplies.