1. All The Cartoon Network Shows Have A Shared Universe
Disney/Pixar weren't the first ones to have a big and unexpected shared universe, all of the Cartoon Network shows (the classic ones, not the ridiculous cr*p that they're releasing nowadays) have one big shared universe that's going on at the same time. And much to our fortune the implications about this goes way beyond what we can possibly imagine. It began with The Powerpuff Girls and Dexter's Laboratory, since those two shows shared some characters (The Justice Friends appeared in both shows) with Dexter appearing from time to time in the other show. Then we have Samurai Jack, one of the best cartoons ever released in which several places from the Powerpuff Girls appear from time to time. Then we have The Grim Adventures of Billy and Mandy, which had a crossover with The Flinstones. Not only that, but they also tend to mention other Cartoon Network programs from time to time. This now connects 3 different shows (The Flinstones and The Jetsons) but in what way they connect with the other Cartoon Network shows? Apparently there was this sort of massive crossover called "The Grim Adventures of the KND" in which pretty much Everyone is involved; Ed, Edd n' Eddy, The Powerpuff Girls, KND, Foster's house for Imaginary Friends, Dexter and a thousand others that I can't remember right now. It was like a kid's version of The Avengers, I never actually saw it since I can't stand the KND but apparently it was pretty good. But here's where things get a turn for the worse: In Samurai Jack the whole world is pretty much destroyed and under the control of Aku, master of evil. Since we see on the show the remains of Townsville as well as many other references to the Cartoon Network universe it appears that all of our favorite characters were killed by the Evil Aku when he ascended into power. The Justice Friends, The Powerpuff Girls, Billy and Mandy...all of them completely powerless against the all mighty Aku. While it's a very dark and depressing twist to many of the cartoons we grew up with, it's still one of the most awesome crossovers in modern TV. I only wish more shows did something like this.