Particularly fascinating, I think, is the effect of gravity on time, which means that wormhole travel would, of necessity, be time travel. Indeed, as Alex Fillipenko of the University of California at Berkeley says, any travel away from earth's surface is time travel, if only in a micro sense. It's interesting to know that, if a correction wasn't made for the difference in the rate of time passage between the satellite that transmits positioning information and your GPS device on the surface, using that device to guide a trip from L.A. to New York would result in your ending up somewhere in Massachusetts.
[i]mage of a traversable wormhole which connects the place in front of the physical institutes of Tübingen university with the sand dunes near Boulogne sur Mer in the north of France. The image is calculated with 4D raytracing in a Morris-Thorne wormhole metric, but the gravitational effects on the wavelength of light have not been simulated.See here.