Seven-year-old Seth sits at the controls of a miniature sub, his sights set on a banded octopus. He zeroes in on the giant sea creature and presses a button. Startled, the octopus begins waving its legs in a slow-motion gesture of surprise. Seth, of course, lets out a scream of delight. "I killed it!" he proclaims in victory. "No you didn't," I explain. "You took its picture."