Today at TechCrunch Disrupt in New York City the Startup Battlefield got off to a quick start. UJAM, a service which lets you take any melody in your head and turn it into an actual piece of music with a few mouse clicks wowed the crowd. But they used a professional singer for their demo. So what better way to prove the product than to get one of the Battlefield judges to sing? That’s exactly what Chris Sacca did.