sunlight in a tube

this is such an obvious idea, i can't believe no-one has come up with it yet. solar collectors on the roofs of office buidings condense sunlight and transport it through fiber-optic cables down to floors below, to be piped into the light fittings. during the day, they could supplement or completely replace fluorescent tubes, the main energy use in office buildings. as long as no-one gets sunburnt sitting at their desk, this is going to be fucking brilliant. my advice: buy stocks in this company, and glass-producers now. sell stocks in energy companies.