THE GODFATHER - Sonny Corleone getting machine-gunned to ribbons at the toll plaza. He may not have been a villain in a film full of them, but I loved seeing this extremely unpleasant man meet a painful end.
Henry and his pal Otis were unquestionably the villains of the film but I still liked the way they dispatched the dude who is selling the used (stolen) TVs. They take one of the TVs and smash it over his head.
Style or anger? In Defiance-80-no one gets kill, but I love how the neighborhood law abiding citizens beat the crap out of a street gang. I also loved how the hero [BELA] send the villian [BORIS] to kingdom come at the end of THE BLACK CAT-34.
The problem with this as in life , we are making judgments on who is the bad guys and who are the good guys. While in life seems are not always so simple. I was going to list one here, but I would never hear the end of it from SOME BOARD MEMBERS and our dear friend the policeman here might castrate me.
Although this seems to have become a discussion about villains getting their final rewards, the original question involved "Comeuppance" and villains "who got what they deserved." So let me cite the slimy Anthony Heald at the end of "The Pelican Brief" when he realizes that his company can't control the news about to get out about the horrible things they've done and he angrily slams down the phone with "You sonofabitch!!!" and we see the gleeful reactions of Denzel Washington and Julia Roberts. Always find that scene very satisfying.
By the way, I'd like to add that I was disappointed not seeing Saruman get his comeuppance in the theatrical version of Return of the King, I left the theater disappointed they didn't show it. Later I found out it was in the extended version.
I can't find a youtube clip of it, but the destruction of Chang's Bird of Prey in Star Trek VI: The Undiscovered Country felt so gratifying due to the unseemly overuse of it in ST:TNG episodes to represent Klingon ships up to the point that ST:VI came out in 1991. After ST:VI, TNG seemed to have developed new Klingon designs for their series.