There are movies where a conversation is shot with an object or person prominently in the foreground sort of blocking part of the scene, but it is meant to illustrate the division between the two characters talking. The one that pops into my mind is Eraserhead, where there is a plumbing pipe in the middle of the shot.

Although not a comedy per se, in Planet Terror there is a scene of two characters embracing and about to have sex, then the film overheats and melts, a missing reel card pops up, then it skips to the house completely on fire. That is probably the hardest I have ver laughed at a horror movie.