I get to be useful!

Ceiling cat is a reference to possibly the earliest generation of memes. They mostly involved cats. Ceiling cat was a popular one of a cat poking its had down through a hole in a ceiling, captioned “ceiling cat is watching you masturbate” or something similar. The odd grammar/spelling is of the same Era, where these cat memes would be spoken in the “voice” of a cat. The most famous example is “I can haz cheezburger”

Leaving Britney alone is a reference to an early Era of YouTube video, where an actor bawling at the camera ranted about how people were being too mean to Britney Spears, a famous pop star. It was hotly debate whether the contents of the video were genuine or acting. Remember, this was before Snopes, even.

I think that was everything?

Count another in these parts of the internet!