If you look closely at the "cursed video tape" footage, towards the end there is an extreme close-up of Joe Lynch's dog Banzai pooping in reverse. Upon first reviewing the episode, the network actually asked if subliminal shots of penises had been cut into the tape as they couldn't figure out what exactly those shots were.
For the joke about "having to add a woman to the writing staff", the three people playing the "staff writers" are actually two of the show's camera operators (Brian Sowell and Aaron Champion) and Holliston's costumer Autumn Steed. In reality there is not a writing staff for Holliston as creator and star Adam Green writes every episode himself.
Producer Sarah Elbert provides the female staff writer's off-camera line about "having a good joke about air travel." This is an inside joke for stand-up comedians that comes from Adam Green's days as a stand-up comic. "Air travel" is a taboo subject among stand-ups as it is considered to be a topic that has been absolutely beaten to death and a bore to include in any set.
Laura's creepy J-horror crawl was shot in forward and then reversed with select frames cut out of the shot to give that jittery and unnatural look to it.
The black and white photograph of the four main friends that is used for the "blurring faces" gag was taken in a photo booth at actor Zachary Levi's annual San Diego Comic Con party. Levi is a close friend of Green's ever since acting in his film SPIRAL and the four main Holliston actors were at Comic Con to promote season 1 when they took the photograph.