It's been brought to my attention that pretty much everyone has a regimen they stick to when responding to something or someone personally annoying them. For example - mine is as follows:
Step 1. Glance at offending person(s) with mild look of annoyance.
This is just to see if they can get the idea that they're being annoying - some people catch on remarkably quick, and aren't as offended as they would be if I used more intense means to shut them up.
Step 2. Rachet up "glances" to patented Nebulous-stare of impassive disgust.
I have a very specific look I use that, when leveled on someone, can generally make them feel ridiculous in a fairly short span of time. It's quite fun. I enjoy it muchly.
Step 3. Speak to the offending person(s) with quiet disgust.
There's an art to this step - it's all about body language. In this case, I'll speak the words politely enough, but I'll adopt a very fake, thin smile while keeping the eyes from the above step in impassive disgust. If they're stupid enough to ignore the above stare, they won't completely connect the dots between words and body language, but they'll get enough of an idea to, hopefully, bugger the hell off.
Step 4. Speak to the offending person(s) with complete and utter contempt, and endeavor not to rip their head off with my bare hands.
I rarely have to resort to this on people outside my immediate family. However. It does indeed happen. I cannot stand it when the above three steps combined don't knock enough sense into the person(s) for them to stop whatever the offensive action is. Now remember, this last step is only used in completely justified situations. I must say, though, this one has proven effective the times I have had to use it.
Honestly, my experience has been that while a few people catch on quickly, most people it takes until Step 2 to stop. About a quarter make it to Step 3, and about 5% actually make it to Step 4. Chances are, if you're annoying me enough to get me to speak to you, and after that you still persist, I'll probably just walk away myself and stop bothering with you imbeciles. But sometimes, it's inexcusable what you say. I'm still royally pissed at a spectacular display of racism I had the misfortune to witness in Algebra 1 freshman year...Never liked the guy. Still sorta hate him. Anyway.
"Sarcasm. It beats killing people."