Some of you are going to hate me for saying this, but the Miz's "Skull Crushing Finale" is actually a very strong-looking move and actually would probably hurt (of course, it would probably hurt your arms, too, but....).
But you also have to go back to a couple of old-school finishers. I'm thinking predominantly of the Figure-4 Leglock, which, if I'm remembering from an old friend who was an amateur wrestler, was actually outlawed as a leghold in the amateur ranks because of the serious damage it could do to a person's knee.
As far as the Rock's finishers, the Rockbottom is a decent-looking impact move and could hurt if done properly (the uranage suplex it's based off of is a legit move), but the Rock (and Booker T) drop people flat on their back (to spread the impact, remember, it's "fake fighting") when an actual uranage slam/suplex drops people across the top edge of their shoulders, impacting the lower neck. The People's Elbow is....really? It's an elbow drop with dancing around, during which, in a real fight, somebody would probably jump up and attack you or just jump across the "fighting arena" and attack you while you are performing your theatrics (*cough* CM Punk *cough*).
wk