DaVinci Decoded

is an excellent book by Michael Gelb (isbn 0-385-33861-9). As usual I'm going to quote from a few pages:
Ritual is the husk of true faith [Lao Tzu]
Poor is the man who desires many things. Neither promise yourself things nor do things if you see that when deprived of them they will cause you material suffering. [Leonardo]
He prided himself on being a uomo sense letter (man without academic training) and a disciepolo della sperienza (disciple of experience).
I shall continue. I never tire of being useful. Obstacles do not bend me. Every obstacle is destroyed through rigour. [Leonardo]
You can have neither greater nor lesser dominion than you have over yourself. [Leonardo]
The average person "looks without seeing, listens without hearing, touches without feeling, eats without tasting, moves without physical awareness, inhales without awareness of odour or fragrance, and talks without thinking." [Leonardo]
Mindfulness is complete attention in the now, rather than worrying about the past or investing in expectations about the future.
The Jewish tradition, for example, teaches that "the key to everything is the way you start."
Fill the space with objects and images that inspire you to remember your connection to something greater than your own ego.
In his anatomical studies, as in everything else he did, Leonardo was always striving for the most all-encompassing type of understanding as well as the most detailed.
Leonardo himself was known to be even-tempered and optimistic, even when life was hard. He was also meticulous in his daily habits of eating, exercising, and resting.
Modern research confirms ambidexterity promotes balance and brain development. Not surprisingly, Leonardo was ambidextrous.