Saver makes references to the author.

Marmalade Boy does this here and there. Funny manga, btw.

Quote from ayameharushino

Quote from tbl

Gintama doesn't just break the fourth wall, it blows it up, pushes the rubble into the see, then salts the earth.

Agree! I don't think I've read any manga that completely obliterates the fourth wall more than Gintama 😀

Only in Gintama are narration boxes viable weapons

"It is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science."