Hot-air balloonists spend big money trying to fly around the world, but so far none has succeeded. Britain's Andrew Byers, 7, has them beat. In June he spent $1.60 on a helium balloon. He attached a note asking the finder to write back, and then let it fly. Last month he heard from Harry Green, who found the balloon a few months ago--in New Zealand! It had traveled thousands of miles farther than any hot-air balloon. Says Andrew: "My friends all clapped."