Astronomers, including Craig Sarazin from U.Va., have discovered jets shooting out at nearly the speed of light from the regions around a black hole, and which are changing their direction rapidly (minutes to hours).  This reorientation of the jets is due to the Lense-Thirring Precession, an effect predicted by Einstein's Theory of General Relativity.  This effect is expected to occur near a rotating black hole, and is caused by the rotating black hole dragging space and time around with it as it rotates.  This is believed to be the first direct observation of the Lense-Thirring Precession