It’s often said you can’t make something out of nothing. Cody Friesen may have come as close to succeeding as anyone. To show me his technological sleight of hand, Friesen invites me to a hillside house in Berkeley, California on a sunny afternoon. There, in a shaded courtyard, we each sample a cup of water that flows from a drinking fountain. The water is cool and delicious – and it was made out of thin air. Literally.