Continuity Nod/Web Animation

Examples of Continuity Nods in Web Animation include:

Homestar Runner has absolutely massive amounts of these. The most minor characters will pop up in various places, turns of phrase and vocabulary items will be thrown around in completely different contexts, objects from previous cartoons will make appearances elsewhere for little reason. At its greatest, a one-off joke will come back so much that it becomes a much larger part of the website, such as the band Limozeen. All you need to do is go to the Homestar Runner Wiki, find a cartoon's page and look at inside references, where each Continuity Nod, Shout-Out, and Mythology Gag will be documented in precise detail.
"Aw, shit. And I was in charge of confetti."^{[dead link]}
- When Grif somehow revived Sarge from a gunshot wound he was chastised for how random that treatment was and Sarge ask if he would have treated a shot in the foot by rubbing aloe vera on his neck. When Grif talks to Doc a while later, a (not very good) medic, Doc tells Grif that he made the right decision and states that he just treated Caboose's gunshot wound in the foot by rubbing aloe vera on his neck (then his toe fell off).
- A more recent one was in Recreation: Grif gets in the cockpit for a large vehicle and ask 'Why are there only four pedals if there's six directions?', the exact opposite of what Caboose asked when he first piloted his team's tank in season 1. There's been several per episode recently, though many are of the "blink and you'll miss it" variety.
- Taken Up to Eleven in Red vs. Blue Revelations.
In Charlie the Unicorn 3, having been through everything else the cartoon is going to throw at him, at least he finds that kidney they stole back in the first one.
This fan work for Watchmen is filled with nods toward the original graphic novel, from Rorsachs' "love of animals" to the scene where the comedian falls out of a window.
Leet World: In "Satisfaction Guaranteed", Player has something of an obsession with a snowman's hat. In the second season, the same hat can be seen in the intro sequence.
In the Dragon Fable quest "The Risen", there's a nod toward the Mechquest side quest where you go to an old temple to look for fossils.
In Brain POP's Fractions episode, many of the robots from other videos on the site, such as Little Jimmy and the Cycloids from the Capitalization video and the Hillbot from the Country Music video, show up at Moby's birthday party.