I really try not to say this phrase to people. First off I don't really go out of my way to directly insult people, well most of the time. Mainly though because if I ask this, sometimes if not most of the time, I get into some one's life story of "this one time I did such and such with you and you said such and such and then you call someone this and then they said that". Ah yes how I love these conversations. So as to avoid this I have developed the following strategies when I encounter a random person and I have absolutely no clue who they are. Feel free to use any of the following.
Oh its you, but sorry I don't have time to catch up right now.
This makes the person feel good, and gives the impression that I would speak with them. This also gives me time to actually think if I know who the hell this person is. If I remember and its good, which in most cases its not then all is well. If I remember and they were some idiot then I of course have the option of never speaking with them again or if it was so idiotic-- I have the perfect opportunity to relive this persons special kind of stupid.
Of course I know you.
You say this when you need to take an afk or you are doing something, which is obviously occupying your attention. They will either a)go on and on and you won't be there to hear it or be able to pay attention, or b)Get so pissed off from you not responding that they will stop talking to you all together. So in either case this is win win for you.
Just play along with whatever they are saying.
This is very fun an effective if you are bored. You will also make their day by actually talking to them. They will go home happy and you will get your own laughs. Also you maybe even remember them by the end. Then could apply all the things from the first one.
Offend them so they will stop talking.
If just flat out ignoring them doesn't work then this is the route you may have to take. Yes this is a real asshole thing to do, but then you if you cared you would have known who they were in the first place. The sky is the limit to how you can insult them. Just make sure its to the point and they actually understand you are making fun of them and not joking around. Since if they think you are joking they will just keep going on.
Make up a story about them being awful.
You really don't need to even say something untrue. It could be something about someone else that you are using to make them look like a tool. This can be amusing on your end and get whoever they are to stop talking. It's a game we play this for fun right? And making some random person spaz out about them not doing something is extremely fun.
Perfect way to get someone to stop talking to you. Log out then back in and they probably won't even notice, since they will probably be trying to talk to other people they "knew".
That is it for today. Congrats Canada on its first Gold Medal on home soil! Enjoy your last day before reset.