Late Night Breakthrough?

I've heard of that happening. Specifically in terms of math/science equations. Some people just "see" the result better than being able to sequentially work their way through. It's a global, intuitive way rather than ytical. There's nothing wrong with it--it's just against the traditional school's ytical, sequential approach to most things. And I've also heard of mathematicians/scientists getting a "Eureka!" as the result of a dream. Seems to me there have been some famous scientists who have had that happen, but it was a loooong time ago when I read this stuff, so the names are gone.