Time-travel continues to exercise its mesmeric fascination upon writers, readers and editors of science fiction alike. Probably because almost all of us, at one time or another, have longed greatly to visit either the future or the past. Perhaps, in view of the dangerous paradoxes such travel must involve, it is a good thing that such horological journeys have to date been confined to the printed page. New neighbors are always exciting. But the anachronistic MacDonalds offered a bit too much.