http://tierneylab.blogs.nytimes.com/2008/11/20/dancing-with-the-scientists/

-- 
"Not that anything had really been settled. All of the questions that
had been open when my head had hit the pillow were still pending. But
in the intervening hours, my brain had been changing to fit the new
shape of my world. I guess that's why we can't do anything else while
we're sleeping: it's when we work hardest."
--Neal Stephenson, _Anathem_