Have you ever imagined painting a piano and then actually hearing it play? It's possible. Developed by an MIT scientist, Colorforms' new Brush With Genius is more magic wand than art tool. As kids use the watercolor brush, they're literally painting with sound. Just dip the brush into plain water, stroke onto a piece of paper and use your finger to create a scale of musical notes. The trick? A unique conducting technology created by an MIT PhD student allows users to create and control sounds as they slide their finger across the brush stroke.