Written over the past nine years, this collection of visionary tales ranges from silly historical musings to hard-core science fiction. Sheffield's gift for spinning scientific and religious issues into rousing and witty yarns is reflected in the Hugo and Nebula Award-winning title story about Babbage Engines, incest, weird aliens, and a knotty problem in modern computing--along with "Millennium," "Trapalanda," "The Bees's Kiss," and other widely praised works.