In the “Reincarnation” episode of Futurama, they broke the episode up into three segments, each of which used a different style.
The first one was in an old-fashioned Max Fleischer style and the main gag was that Fry accidentally created a new color unlike any other color previously known, which of course we couldn’t see because the segment was in black-and-white.
The second act was in 16-bit video-game style—which Community had recently done—and the gag was that the professor’s fancy microscope was able to zoom to a super-microscopic level, allowing him to see the smallest form of matter in all its “beautiful, intricate, detailed” glory and thus allowed him to discover a grand-unified-theory. The gag of course being that because the segment was in 16-bit, we could not see the detail the professor mentioned and only saw a single pixel.
The final part was in anime style. I did not notice any specific gag about something that we would be unable to see because of the style used.
This page mentions a communications issue between the two races which seems like it could work because of how anime programs are (poorly) dubbed into English, but that would be pretty weak compared to the previous two. It also mentions Zoidberg doing an intricate dance, but the camera simply panning over him standing still. That really sounds like the second one, but I don’t see how it has anything to do with doing the segment being anime or why it would have been different had they done it in their normal style.
Does anyone know what the third gag was (or if there even was one—which would really surprise me if there were not).