If there was that one video game character you could punch...

[Lilly]

Joker from, specifically, Batman: Arkham City.

Except you do get a chance to punch him later on in the game...sort of, kind of a huge spoiler there. :#

Another character I think I'd punch would be Shepard's biggest fan in Mass Effect. I mean, you get to shoot him in the foot later in the sequel, but still no punch option! >:( I hope we finally get to sock him hard in Mass Effect 3, that'd totally make my day.