Yea, it was really great, one of the most obvious ones when this thread popped up, or should i say - his right hand comes to mind before most on this subject!
Thomas Hearns had Knockout power in his right hand, Roberto Duran fell face flat on the canvas after suffering a right cross from the Hitman.
David Sotelo deserves a mention when it comes to big right hand punchers. Not a great fighter by any stretch, but he was tough, durable and came to fight and he could have flattened many a great fighter had he landed that sledgehammer right of his on their noggin.
Would have been my pick, as far as KO potential, but I liked Robinson's and Ali's too, for speed and accuracy and beauty, and they had some sting. And just thought of Jersey Joe Walcott's off of his lateral movement; the way he suckered bigger men into that shot, (most notably the aforementioned Louis), was a thing of true boxing aesthetics.
Hearns, Spinks, Arguello, Duran, Ali, Lewis, Monzon, Hopkins, Mayweather, Robinson, Louis are my top choices. Hearns, Spinks, and Arguello for the top 3.
Mark Breland in the ams, but it didn't quite convert to the pro's. Infookingcredible right hand in the amateur ranks.