Chongster has hit some really good points here.
Another recent example: "Krabs a La Mode," when Plankton gets swallowed by the old guy. While Plankton's line "In 4 to 6 hours I will get my revenge" is clever, the implication is a bit gross, when later the toilet flushes and we see a wet Plankton opening the bathroom door. There's a good example of "gross" if I ever saw one!