Abstract Mathematics Revealed In Dreams

While on his death bed, the brilliant Indian mathematician Srinivasa Ramanujan cryptically wrote down functions he said came to him in dreams, with a hunch about how they behaved. Now 100 years later, researchers say they've proved he was right.

http://www.livescience.com/25597-ramanujans-math-theories-proved.html

I recall reading that Einstein also came to revelations in theoretical physics, that he knew to be correct, but couldn't prove mathematically. After his death, an autopsy revealed that Einstein's brain structure was quite unusual, which might explain his brilliant, if non-linear, deductions.