The Jackson and Ankiel throws are great comps. But the Jackson throw was the best I've ever seen because he was throwing from a flat-footed start. (IIRC, Ankiel had his momentum behind him as he lined up the throw.)
The one that comes to mind from my youth was Roberto Clemente in the '71 series. There was a fly hit down the right field line and when Clemente caught it he had his back almost turned to second base. But because he knew the runner (Merv Rettenmund) would be tagging, he wheeled completely around and threw in one motion.
The only video I can find of the throw does not show the play in its entirety. It begins at the 1:20 mark in this video and stops right after Curt Gowdy exclaims "what a throw!"
https://www.youtube.com/watch?v=I1k5ozCUpcI
What separates this example from others is that Clemente is not using a full windup and he's not moving forward when he makes the throw. Indeed, his momentum is taking him away from third, and yet he gets the ball there on a line.
From the same World Series, there was also this slightly less impressive throw to stop a run from scoring.
https://www.youtube.com/watch?v=0UUy65ZpSP0
Roberto had a cannon out there and he combined it with one of the quickest releases in the game. A shame that relatively little video exists from his youth to make the case.
