A number of the bits on Wha-Chow! Your Mileage May Vary, and it helps that it was this troper's personal introduction to the realm of internet humor, but they can indeed be hilarious. The slogan of the show is "It's like a kick in the nuts!" for a reason.
Many of Cailen's bits. Too many to mention.
The "Vic Mignogna" Help Hotline, his version of a suicide hotline done in Vector the Crocodile's voice, instructing hopeless fans of Vic Mignogna on how to kill themselves. This lead to several of his friends who were listening to the show live to call his phone in the middle of the show for cheap laughs.
A later episode has Mankey (a buddy of Psy's who goes by The Wise Mankey, not the Pokemon.) talk about how he went to a Vic Mignogna panel and actually told him about the Vic Mignona Help Hotline, then gave him Cailen's number. Unfortunately, he got his answering machine, but it was still hilarious.
Cappella saying the show's slogan as Silver
Doug Walker derails an otherwise serious interview
TWICE. With Lindsey and Linkara coming in unexpectedly.
"Personal %$&@ You's"
Reading of fan-submitted fanfic lemon scenes (Usually purposefully bad, but that just makes it better)
The Running Gag about Tristan from Yu Gi Oh The Abridged Series and Bill Cosby being in a homosexual relationship.
I work off of a FUCKING picnic table in the middle of the FUCKING office next to the FUCKING fax machine and it FUCKING PISSES ME OFF!!
You give good head Jaden. I love you.
The Whole! Damn! Reading! of the "Love In The Forest" Pokemon fic. Linked to the Wha-Chow cast by The Wise Mankey, a "former Ash and Misty shipper" when LittleKuriboh made a deal to read a hentai fic if the show had reached 400 viewers during one of their live shows. It started with such gems as sitting on Gravelers, to Ash kissing Lickitung, and the narm filled love confession, which all was in the actual writing, to when they decided to change the characters from Ash and Misty, to Yami and Jaden respectively. As the fic went on, becoming increasingly disgusting and funny due to the cast's reactions to everything, more lines came up such as "You are a wonderful c*$# sucker Jaden" to "Here comes the mine digger!" Both said by LittleKuriboh in Yami's voice.
The largest amount of humor and disgust came from the last reading when Doug of That Guy with the Glasses and Shady read on taking the place of Ash and Misty respectively, with Martin LittleKuriboh narrating the damned thing. Except they ended up replacing the characters with the ones that are reading the quotes. The first line of the reading in that episode is Doug: "Do you want go with the grand finally and have pleasure filled sex right now?" Martin: "Asked Doug already knowing Shady's answer." It goes down from there.
The only way to truly appreciate and be disgusted by the whole thing is by going to the main Wha-Chow site. It starts from Poop Downunda' to The Nostalgia Critic, the Nostalgia Chick, and Linkara.
Related to the above: The ENTIRE episode of The Nostalgia Critic, the Nostalgia Chick, and Linkara. The interview was both fun and informative at the same time, the Personal Fuck You's were all hilarious (especially when Doug read the one about 3D movies in Chris Tucker's voice), Sounds Good ended up solidifying "birds and Mario" as a running gag (made even more funny because it was completely unintentional), and as noted above, the climax of the porn reading that Crosses the Line Twice when it's Doug and Shady. Up until that point everyone was expecting Jaden (even Shady!).
In fact most fanfic readings on Wha-Chow have a few good laughs, others have laughs through the whole damn thing.
Two words: Horse Party.
For other non-wha-chow pieces of hilarity, there's also some of Psyguy's videos. His most recent series he's trying to start? "Rage Quit" for reviews (a sequel to previous random events videos when playing video games) and its byproduct "Press B To Win" for Smash Bros. Here's most of them.
If i may expand upon that episode, there is a particular segment with some supreme improv work, all brought on from an unintentional flub. It being an April Fools episode, the cast were doing different voices for its entirety. Psy as Renaldo, Kirbopher as Tails, Martin as Tristan, Niro as Bill Cosby (hence the name and art), etc. Psy makes a joke that makes Kirb choke with laughter, with which Martin pushes further and Kirb decides to make his voice lower as he continues reading. And lower. And lower. Until it's just demonic garbles. Amazingly, Martin and Niro are able to work with it and the three stay in-character and work the scene to a conclusion. However, Psy's failed attempts at masking his laughter throughout just make it all the more funny. At one point in his fit he blatantly tells the audience "I can't do this!" and "Oh my god, there's 100 people in the chat, why the hell are you guys all here?!"
Essentially, all of the episode with special guest Egoraptor. To wit: It starts off talking about how Egoraptor was raped by a dude, not a guy or a man, a dude, as in a surfer dude. It only goes uphill from there, such as his reactions to Psy's asinine questions,but the highlight is a PFU read by Egoraptor in the Solid Snake voice.
In "Keith Richards directs you to Whachow", Niro relates a story how Kirb called his cellphone in the middle of sex, a joke later revealing how he did the same to several other people in the podcast which lead to the group presuming that Kirb had "Conjugal Clairvoyance." LittleKuriboh joked bringing up a mental image of Kirb outside a bedroom with two people having sex, peering into the window, and asking if they're "Skypeable."
In "Paradigm Shift BRB", a fan/stalker from the show's U Stream chatroom PM'ed and attempted to call LittleKuriboh on Skype, constantly pestering him and asking to be on the show during the broadcast. Eventually she somehow was included in the show so the cast would humiliate her. After being initially let in, seconds later she said "I'll be back soon, be right back." This drew the ire of Liz and Kirb. What made things worse was that she did it again after Liz started to verbally tear into her. Her actions inspired Shady Vox to declare her the "best troll ever" and everyone else in the show started mocking her saying "be right back" at the end of all their sentences until she was eventually kicked out of the chat for casually admitting to "have no sensitivity."
Back in Grats on your Cosby, all that must be said is George Takei as the Joker and George Takei vs Motimon (from the Abridgimon episode)