"Bread Overhead" is a story Fritz Leiber could have written to send up today's bewildering bread aisle -- all those claims of low-cal and low-low-carb. In fact, the story probably reads better now than it did in 1958, back when the choice came down to white or whole wheat. Leiber slyly imagines a near-future when giant machines not only harvest the wheat field, but grind flour and bake bread on the spot -- the ultimate in big farming. In this toasted tomorrow, the highly-mechanized Puffy Products is bent on producing the supremely lightest loaf. The story is what happens if bread isn't just airy, but pumped full of lighter-than-air helium. Leiber ("Ships to the Stars") didn't often bake up such a souffle of spoof, but he's a master in the kitchen. And "Bread Overhead" has just enough to say about human nature to be filling, besides.