Like many of you have heard of there being hidden sexual stuff in certain disney movies, Nickelodeon has done the same, but in a far worse degree. This stuff has been shown in shows like Rocko's Modern Life, Rugrats, Ren and Stimpy, and Sponge Bob.
Rocko's Modern Life is the most abundant in sexual innuendo of all of the cartoons I've mentioned. Here's the Wikipedia article that lists every incident in the show regarding its innuendo:
Link
In the Rugrats episode where the Pickles family goes to the county fair (Its one of the old episodes. I remember this from way long ago), there is a brief moment where you see a trailer with its door open and on the door you see a pinup of a topless woman.
In Spongebob, there is one scene where he's watching TV and it shows an orange dancing sea anenome. When Gary slithers into the room, Spongebob quickly changes the channel and says, "Gary, you're not allowed to watch these shows." Spongebob was obviously looking at sea creature porn.
Im sure there's more stuff like that in other shows, but I don't really watch Nick anymore. Anybody noticed anything like that in other cartoons? Discuss...