Seems like it's been a few years since we mentioned light shelves. Groovy, simple things they bounce external natural light deep into building reducing the need for powered, artificial illumination. But they do have their limitations, as the ever excellent Environmental Building News, in a product review for LightLouver Daylighting System, observes. "In order to effectively protect an indoor workspace from direct sunlight, [light shelves] need to be quite wide, and they rarely reflect light deep enough into a space to daylight more than the perimeter zone." Not so with LightLouvers. Roughly speaking the units are like thinnish louvre blinds with a bunch of fixed panels, shaped a bit like the Nike 'swoosh' logo. Apparently the angled blades reflect about 76% of direct sunlight into a room, up onto a ceiling, reaching much further back into the space than the usual light shelf. On overcast days they are said to throw around 54% of the available light inside. A retractable version and one built into a glazing unit are also under development. The current model costs upwards from $30 per ft 2 ($300/m 2) and as one of the clients who have them installed says, "You see a nice amount of light on the ceiling, and it reflects down into the workplace—they are doing what they are supposed to do." ::LightLouver, via Environmental Building News, who have some other good pics.