And then we have the to-do list to make you feel like the laziest, stupidest, no-good lay-about ever. Or maybe that's just me. This from NPR: "Here's something you can't do every day: How about you and I slip into Leonardo da Vinci's head for moment? Deep in. Thanks to historian Toby Lester, we can. In a book soon to be published, Lester says Leonardo used to travel with a small notebook hanging from his belt, and "whenever something caught his eye," he would make a note, or begin "sketching furiously." "It is useful," Leonardo wrote, to "constantly observe, note, and consider." But when you are Leonardo, what sorts of things are buzzing around in your head? Well, Toby Lester describes what is essentially a "To Do" list buried in one of those notebooks, a bunch of things Leonardo planned to do one week, or month, in the early 1490's."