The trouble with TED.com is that there's literally way too much that you can see and listen to there. So I'm constantly running across new vids and talks that apparently everybody in the world knew about but me. This is probably one of those: in which artist Siegfried Woldhek takes you through how he used a bit of deduction to come up with what he thinks Leonardo da Vinci actually looked like. Because even though Da Vinci probably had schematics somewhere in his notes for a digital camera, webcam and YouTube, he never actually executed on any of the projects. Hence the lack of certainty.