'Ever' is a bit tricky, being limited by memory.
Jess against the huns and Smith v copenhagen are good shouts.
Zerouali's free kick (against hibs?) out near the touchline when a couple of players were standing over it discussing what to do, and he just comes up and sticks it in the net without consulting them.
Andy Dow v Hibs in a cup semi 1999ish. Not spectacular but very well worked. We had a free kick out wide on the right. Stavrum, having stepped behind his marker signals that he wants it played over his head then, as it gets played, backs quickly off his marker to where the ball is going to land. The defense panics and tries to close him down but rather than shoot he cushions a volley back into the centre for the waiting Dow to lash past the keeper. An example of Stavrum's football brain, and why he was so useful.
I doubt these are the 'best', but they immediately jump to mind, so must have something going for them.