Deep down no one wants to throw up in front of their friends or enemies after a night out. It's embarrassing, it's disgusting, and it really ruins a make-out session. But if you're drinking properly it IS going to happen, therefore the best you can do is come up with a few decent explanations for why you threw up to say IMMEDIATELY in order to save face.
10). I'm bulimic. - Now being bulimic is nothing to be proud of, but at least it makes you a sympathetic figure and not just someone who sprayed partially digested birthday cake and Dewars all over a bartender's face.
9). I think I ate some bad pork. - Blaming the vomit on something you ate is better than admitting your body was rejecting the poison ethanol. It usually helps to have whatever you're talking about in the vomit though, so if you're going with pork, eat a few strips of raw bacon before going out so it's visible in the sick.
8.) I wanted to give the pigeons some food. - If you're in a city there are probably pigeons and pigeons DO eat human vomit.
7). It's National Throw Up At Work Day! - There are tons of these stupid ass "Dress Like a Pirate" type things going on these days so this is a good one to use at work after a hangover.
6). I was just thinking about the Holocaust. - Not the best one to use at a KKK rally, but anywhere else and it would be completely understandable that visions of a heinous tragedy would trigger regurgitation.
5). Text the word REDCROSS to 90999 to donate to victims of Hurricane Sandy. - Once you throw up in a public place there's a good chance you're in the spotlight so why not use that time to help others?
4). I was just thinking about the time I fucked your mother. - This one is like the Holocaust one, but better if you're around someone you want to insult.
3).This alcohol does not meet my body's standards of excellence! - This is a good one to use in a British accent if you're trying to seem sophisticated, which is usually difficult to do when you're clutching a public toilet bowl that may or may not be covered in another human being's feces.
2). That dinner was so nice I'll have to eat it twice! - Only say this if you're willing to eat your own vomit. It's gross and people will either leave or take pics to post on Facebook, but it turns your embarrassing moment into a sideshow act not unlike geeking a chicken so if that's what you're going for, have at it!
1). I had to empty my stomach and I don't have time for shitting. - Pretty self-explanatory, it makes complete logical sense. A perfect argument.
Alright there's ten pretty decent things to say or yell after vomiting. Come to think of it, you don't even need to have been drinking. Throwing up in public is embarrassing no matter what happened before it, drinking or horrible stomach virus. I hope these work for you.