I'll vote for the Avro Arrow. It's a crime what Diefenbaker did, overnight 14,525 people were laid off. Our loss however was the United States gain (and many other countries for that matter). Without the Avro workers that went on to work as NASA, who knows if the US would have fulfilled Kennedy's dream of landing a man on the moon by the end of the sixties. We Canadians are left to wonder what might have been.