Leonardo Had A Very Big Brain Indeed

This is from a poster advertising an exhibition of Leonardo Da Vinci drawings and etchings at the Queen's Gallery at Buckingham Palace. I just noticed the window behind it and imagined he was so bright you could see his thoughts and ideas in visible brainwaves!
My brain feels exactly the opposite at the moment after a week of work and commuting - all I want to do is drink wine, eat pizza, watch crap telly and fall asleep on the sofa! Thank God for Fridays.