Back when I was in my late teens I knew a guy with a pet hamster. When a bunch of us would have a few beers at his place on a Saturday night, he would always put a separate drinking bowl in the hamster cage and fill it with beer, as he felt it was only right that the hamster had fun too.
The little fucker loved the stuff, it would guzzle it all immediately. It would stagger about it's cage afterwards before falling asleep/comatose, and later when it woke up it would drink a ton of water, probably trying to get rid of the hangover.
Given how animals deliberately seek out fermented fruit as another poster mentioned above, it's safe to say that your parakeet will love getting drunk.
I'm not sure how it would affect his health, but stop letting it stick it's beak in your mouth you dirty bastard!