And to those of you who aren't aware of other explanations for this outside of "a supernatural occurrence", then here's one;
"Paul Doherty, senior scientist at the Exploratorium in San Francisco, believes the statue's movement isn't caused by any supernatural force, but by something quite ordinary: vibrational stick-slip friction, sometimes called stick-slip vibration.
As Doherty told LiveScience, if the glass shelf on which the statue rests vibrates even slightly, "the vibrating glass moves the statue in the same direction," causing it to turn around.
An everyday example can occur when someone uses an electric blender on a kitchen countertop: The vibration of the blender can cause a nearby coffee cup to "walk" across the countertop.
But why would the statue stop moving after turning 180 degrees? Doherty believes the statue stops turning because it's asymmetrically weighted: "One side of the statue has more weight than the other side." After turning around on the shelf, the statue's uneven bottom reaches a more stable position and stops turning.
Besides the footsteps of passing museum visitors, the source of the stick-slip vibration "could be some trolley that goes by during the day, or a train that passes during the day," Doherty said."
Still pretty cool that it should happen to an Egyptian statue, of all things. :-P