Bret Victor - Inventing on Principle

Bio: Bret Victor invents tools that enable people to understand and create. He has designed experimental UI concepts at Apple, interactive data graphics for Al Gore, and musical instruments at Alesis.
For more Bret, see worrydream.com
Victor demos some great looking software that connects code to the visual, making the creation process more visceral, and he finishes up with worhtwhile thoughts on the invention process.
http://vimeo.com/36579366