Incestuous Casting: Harry's sister Holly played one of the porn stars in 'Hal the Misinterpretive Porn Star'. Harry himself played Hal.
One of Us: His knowledge of Internet pop culture is unassailable, given his subtle incorporations of Sonichu in his animations and his fanart of the elusive Amber Lamps from the Epic Beard Man viral video. In his Skyrim video he shows some characters from Zelda in their CD-i counterparts, which can only mean he's either played them too or also entertains the occasional Youtube Poop. And the backward, satanic sounding message at the end of "Twitter Twatter" is actually "I choose you, Bulbasaur!"