Slashdot linked up this nifty solar-powered lighting device that could be coming soon to an office near you. And when I say solar powered, I'm not talking about a panel providing electricity. The system uses fiber optics to transmit actual sunlight into a building, although some models are planned to include electric lights to supplement the natural light.
Office lighting has never made much of a difference either way to me, but there are probably half a dozen folks with interior (non-window) offices here who go to great lengths to create a more "natural" light in their workspace. Usually the effect is pretty cave-like, so there might actually be a very large market for this sort of device.