Usually, wistful nostalgia for pop culture trinkets of days past is reserved for things that existed before 1990, but not for Nickelodeon fans. This week marks the 20-year anniversary of the premiere of three of the network's seminal cartoons—Ren & Stimpy, Doug, and Rugrats—and while the channel isn't doing anything to celebrate, legions of young fans certainly are. Let's take a little trip down memory lane.

Ren and Stimpy, of course, was the first of the gross-out/clever cartoons that later gave way to shows like Beavis and Butthead and South Park. It was ostensibly aimed at children, but the gleefully gonzo plotlines were just as attractive to immature adults. Take a moment to revisit the show's unofficial theme song, "Happy Happy Joy Joy":

The less deranged Doug has spawned an astonishingly large collection of tribute videos and bizarro fan art. Arguably the best part of the show is the occasional cameo from Doug's favorite mop-topped band, The Beets:

Rugrats proved so timelessly popular that it actually spawned a spinoff, Rugrats: All Grown Up, three feature films, and it is the only Nickelodeon show to have received a star on the Hollywood Walk of Fame. Also, it gave birth to the Rugrat Rap:

Again, while Nickelodeon isn't planning any special programming to commemorate this momentous anniversary, TeenNick did just start airing their special late-night programming block, "The '90s Are All That," featuring all three of the above shows and more late-century favorites from the vault.