I got a few that made me go crazy in Katekyo Hitman Reborn! in the more recent chapters.
Reborn looking like a badass
And Reborn talking like a badass
I'm a little obsessed with that manga...so I could end up posting page after page from that.
And I wasn't able to single out a single page, so I'm just gonna say any one of them in Fullmetal Alchemist make me have fangirlish moments...yeah...that manga is one of my all time favorites.