It's hard to help, not knowing what the discipline you're using is and why that might not be working for him.
Generally speaking, it sounds like whatever you're doing - whatever you're taking away, for instance, or the fact he's being sent to his room or whatever -- isn't his "currency." The idea is to find what's "currency" for him -- what he really values so much that losing it affects him. If you're taking away (again, just for instance) his TV time for the day, and he doesn't really care about watching TV all that much, you're not removing something he values, so he doesn't care. If he's being sent to his room but his room is full of stuff he likes anyway, his books or toys, then he's not losing anything through that form of discipline.
Figure out what he would most regret losing and want to win back so much that he would feel, for lack of a better term, the pain of losing it temporarily. Meanwhile, please do not ever let him see that the laughing makes your blood boil -- you may feel that, we all would, but don't let him SEE it! Stay as cool as ice if you possibly can. He will soon learn he can't get a rise out of you by laughing.