Meta-narrative manga recs

[PantsMan]

I'm in the mood for any "meta"-sort of manga you might have come across. From stuff with a lot of surreal, panelling jokes, stories revolving around odd visual gimmicks or even just something with a plot about characters knowing they're in a story and how they react to it.

Doesn't have to be particularly experimental either. As long as it's more involved than just a throwaway "Think of our readers/editors!" 4th wall gag, I'll give it a try.