The French "détournements" like La Classe Américaine & Message à Caractère Informatif
(exploiting the fact that most non-French things are dubbed in French, they redubbed cut-up films and training videos with utter nonsense)
But also misheard lyrics
Not to mention "literal versions" of music videos
And now we have "as interpreted by a bad lip reader", who starts with a clever take on Rebecca Black's Friday :D
Pop culture + nonsense + playing with language, I suppose ;)
I could probably fit into that Chris Morris' Bushwhacked, Engrish and the incredibly popular Damn You Autocorrect.
Talking about "playing with language", I'm currently working with the Natural Language Toolkit (together with Lionel), that's damn fun/exciting/interesting :D