One of my most memorable kills vs another gv happened about a month ago.
I upped a King Tiger at a port after a report of "a lot of tanks are inbound to Port XYZ", I rolled out and went near the center of the field and stopped on the concrete, pivoted in place putting my front towards the enemy spawn, and shut off the engine. About that time I spotted a round inbound from waaaaay out there. I zoomed in and saw the culprit: a stationary enemy Panther (or so I thought). Using the German "mili-radian" sight I gauged the enemy tank to be about 3600 yards out and slightly elevated from my position. I fired and watched the shot arc out towards the target, got up and made a sammich and grabbed another beer real quick like, and sat back down in time to see the round impact dead square on the frontal armor followed by a flash and a plume of black smoke. Immediately following the impact a message in the chat bar popped up saying "You shot down prowl3r". As I tried to gather my thoughts on what just happened, I get a PM from prowl3r himself giving kudos to the nice "long range 1 shot kill vs a King Tiger".
I've made some very long shots properly using the mili-radian sight, but that one is the furthest and the best (and most lucky) considering the distance and being "first shot on target".