During a SW novel entitled "The Bounty Hunter Wars", Vader utilized his TK to begin force-choking Prince Xizor from tens of thousands of light years away (Vader was near Coruscant, and Xizor was on Tatooine.) What makes the feat even more impressive is that Vader was stated to be immensely holding back at the time, as to not show Palpatine what he was truly capable of.
That is easily the best TK feat throughout the entire SW mythos. Vader using his TK in such a fine-tuned/precise manner across such a VAST distance. Truly insane.