Basically a solar collector /concentrator on top of a very tall pipe that goes beyond the cloud cover to collect sunlight for your building.
The pipe would have to be _very_ sturdy and have a large light concentrator on top of it.
This might be practical for a skyscraper, or implemented as a tower in a small, northern town (with typically low cloud cover) to re-radiate the sunlight from the appropriate (below-the-clouds) height on cloudy days.
Inspired by the link-- cowtamer, Nov 14 2008 Seasonal Solar Lighting Seasonal_20solar_20lighting [cowtamer, Nov 14 2008] Light Tube http://en.wikipedia.org/wiki/Light_tube [cowtamer, Nov 14 2008] Something to watch out for when you set up a solar collector is the energy used to make it, which can so easily exceed the energy you will collect over a typical 20 year life span. For a simple solar panel this is not a problem. For what is essentially an additional skyscraper on top of a skyscraper, it might be.-- Bad Jim, Nov 17 2008 Would it go on top of a mountain?-- Mony a Mickle, Nov 18 2008 random, halfbakery