Foe Yay: Jinx and Kid obviously but it also springs up between her and See-More with different implications and results.
The Web video series
Approval of God: In Fredrik's first Mistakes video, he stated that _9MOTHER9HORSE9EYES9 thanked him for making the episode of Down the Rabbit Hole covering The Interface Series, and that he got to have a talk with GabbiKat (a redditor who helped collect the scattered posts that the series was made out of) in one of the threads.
Funny Moments: His livestream of "Empress Teresa". Knudsen was neutral in his Dt RH video on the book and its author, but he proceeds to demonstrate what he's like when he isn't being objective, going over the bizarre insanity of the book that only increases as it goes on.
Hilarious in Hindsight: In the Mother Horse Eyes video, one of the images shown in the video depicts a link to Wikipedia's article on Time Cube. Fredrik would cover that topic in one of his later episodes.
Memetic Mutation: After mispronouncing the word "Gunshy" as "Gun-she" during his first Channel Awesome Livestream, his fans latched on to the idea of an anime titled "Passion Gunshee."
Misaimed Fandom: Some people interpreted Noah Antwiler (Spoony) as being essentially a critique on Noah's character in the same way DarksydePhil was. As Knudsen made clear however in a subsequent livestream, he in no way thought that, and instead presented Noah more as a tragic victim of his own mental illness.
Nightmare Fuel: The Mouse Utopia Experiments deal with a scientific experiment involving placing mice in what was supposed to be a utopia, only for it to devolve into a hellhole years later, with the implication that the same thing could happen to humanity as a whole if the problem of overpopulation isn't resolved.
Sonichu and Christian Weston Chandler: Always maintain your privacy and never give out your personal info. While the trolls are no doubt responsible for turning Chris's life into what is is now, Chris himself played a major role in his life deteriorating since his discovery by the trolls by nonchalantly giving out his information, thus giving more of the trolls his personal info to use against him to the point that his life is now controlled by the trolls.
DarksydePhil: Respect other people's opinions. While there are some opinions that just can't be agreed with, most of the time, you should respect others' opinions. Even if those opinions criticize your work, it's better to at least listen to them and take advice from them as opposed to outright blocking and insulting those people, as doing so could ultimately lead them to expose who you really are.
Rajneeshpuram: Be careful with your idealism. Pay attention to who you aspire to. If you follow blindly without questioning the judgement of the people you follow, you might end up vulnerable to being manipulated and exploited by other followers (or even the people that you follow) for their own benefit.
Noah Antwiler (Spoony): Fame is never an excuse to act like a jerkass and dodge responsibility. This is made all the more poignant when LordKaT called Spoony out for ruining his chances at getting an interview at GDC due to Spoony's behavior at E3 and LordKaT being associated with Spoony.
The ending of the Collyer Brothers. Langley accidentally triggers one of his own traps crushing him under the pile of junk and his blind and immobile brother starves to death, both alone in their apartment and only being found out weeks after they died, and their apartment is condemned and demolished.
The ending of the Time Cube episode. Gene Ray's disciple Richard Janczarski commits suicide after struggling for years with mental illness and being rejected by his idol, Gene Ray himself dies of old age, the website goes under, and there's the fact that Gene Ray served, in hindsight, as an example of how the internet would soon target the mentally ill and the eccentric for the sake of entertainment.
The whole of Noah Antwiler (Spoony), especially if one was a fan that has watched the rise and fall from the start for themselves. Worse is that, unlike say, DarksydePhil or Norman Boutin, Noah is framed as egotistical and causing his own misfortune, but also as a victim of his own mental problems that eventually broke him down over time.