One rare example of myself realising that I'm drunk, speaking with surprising clarity to a just as drunk friend:
"You know, whenever I'm drunk, I've got a little man in the back of my head. And he's speaking all the time, telling me, all the damn time: 'Patrick, you're drunk! You're acting like an idiot!' He's going on and on about how silly this all is and how stupid you all are. Now give me a beer."
At least that is what I was told I said. Needless to say, my "little man" has become a kind of meme amongst my friends.